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MG MGB Technical - Starter motor issues 71 BGT

Hi,

New to group have a question just got my new old car. It's a 1971 MGB GT took it out a few times just for a run and second time out when restarting the car had a whirring noise so first suspect starter motor checked it once out of car running real slow so rather than mess about got a new hi torque one. Replaced this - well I got a mobile mechanic as I dont have the correct trolley jack.

Anyway same thing no go so looked at battery 11.6 but as I had tried to start car without success it wouldnt be fully charged.

Had a jump pack tried that also a good battery from my Spitfire still same result so anyone have other ideas to try thanks for looking .

Regards
Paul
PW Creswell

Hi Paul, welcome.

If you connected the jump device and spare battery to the existing battery(s) and/or their connections and main cables then that might be the problem.

I'd start with checking the cables and connections (inc earths).

For any starting of the car and testing and fault finding, particularly electrical, you want the battery(s) to be good quality and in good working order and fully charged, the battery posts, clamps, main cables and connections all clean, secure and protected (including all earths of course) - the chain is only as strong as the weakest link.

Batteries are one of the most oversold parts on cars but if they're unreliable, especially within the first year of ownership, I'd not give them a second chance - but often if the electrolyte level is checked, posts clean and battery(s) fully charged up, slowly, then they can be fine.

Modern chargers often say the battery has had it when it hasn't, an old analogue (with dial) charger that works at lower amps will successfully revive the battery where the modern charger won't even bother.

Modern cheap digital multimeters I've found to be very unreliable too.

If you have the patience a battery conditioner (usually used to keep the battery topped up when the car is in storage/garaged/not used) will fully recharged the battery(s) but it might take a couple of days but will do a good job. I've revived a couple of neighbours' batteries this way where their modern chargers have failed (and a mate's jumper pack failed on one of those too).

Don't think I'm an old fart that's all for tradition and against modern stuff, I'm an old fart but all for anything that makes these cars more daily useable and easier to maintain - and use all year round.

BTW - I've an uprated starter and alternator on my car, and a fully electronic dissy, not just top part, I'm dead against unreliability (well as much as you can with these very overpriced old British cars) and farting and fiddling with these cars.
Nigel Atkins

It would be odd for a starter to make a whirring noise as a pre-engaged, but perhaps it was chattering which is a sign of insufficient power.

You have to connect power to the starter motor correctly when it is out of the car or it will run slowly, and it's not really a good test anyway when it's not trying to turn the engine. But if you replaced it and it's the same, it's not the starter.

11.6v at the battery when it wasn't powering anything (if that is what you meant) is very low, and would probably drop a lot further when you turned the key to crank, and cause the chattering.

Then again if another battery and a jump pack didn't work either it's not the battery.

Either with jump pack or a good battery monitor the voltage at the battery posts when you turn the key to crank, and again at the starter battery cable post and body. Any difference between the two is voltage lost in connections. If it's just a volt or so that would be good, a couple of volts is pushing it, more than that definitely needs more investigation. With a good battery cranking a good starter and turning the engine you should see about 10v.

Don't forget the link cable if you have twin 6v batteries, that can have bad connections as well.
paulh4

Seems good advice perhaps the issue is just connecting to the old battery which has been in car perhaps two years and not being used so maybe if I change the battery to the one I know is good and vice versa and try to start my spitfire with the battery from the mg see what happens I mean if it's just a battery that is a easy fix
PW Creswell

Two years of standing won't have the battery at it's best.

If it's a single battery does it have and numbers or labels on it to give you an indication of its age and (initial) power. Sorry on a quick search I couldn't find a decent UK vid to show you about date and other info.

Some owners put in cheapest or any available battery rather than the correct and/or good battery especially for an unused vehicle or one to be sold.

No disrespect to you but check your Spitfire battery is as good as you think and anyway fully (slow) charge it before you use it as a test on the B.

Always test any piece of testing equipment before carrying out any test (guess how I know, more than once, especially if borrowed).

A number of times I've been told the battery is good when it isn't, or battery or other connections are loose, furred up or poor - and it was fine on the car I took it off.

Batteries (or their connections) are always high up in the top ten causes of car breakdowns and it's rarely the battery (if ever?) at fault but the driver or owner at fault with their care, maintenance, attention to the battery.

Modern made batteries are very rarely faulty and you don't need to smear the posts with anything anymore (some overspray to protect post clamps but not directly the posts under the clamps).
Nigel Atkins

Paul - lots of good advice - Nigel's point - with these cars the weakest point is the earth link, whatever the reason for the current prob you will be rewarded by fitting an earth where you can see it - in the engine bay.
Congratulations on your step up - it will be a lot of fun.
Roger
Roger Walker

ETA: Before when I put about first year of ownership I meant ownership of the old car called a classic and ownership of possibly its very old or unsuitable (to vehicle) battery.

Roger, a step up would be a Spridget!

Both I'm only joking having owned both Triumphs and MGs I know they're both good and very bad in many ways with many same faults, and different faults, to each other - obviously if you want a good and reliable car you buy Japanese (had those too so know for sure). :)

Triumphs are the better looking of the two marques.


Nigel Atkins

Well lots of good sound advice although I'm in my late 50,s I have only been driving for 6 years late starter but this will be my fourth classic had a 68 minor and a 68 herald learned a bit on both of those lol like what not to do thanks for all the advice I am pretty sure the battery on the spitfire is good I only got it last September drive the spitfire every chance I get all through the lockdown I was working in hospital took the car almost daily so hopefully the battery is good will of course check the voltage before I take it out
PW Creswell

Unless you've got lots of extra modern electronics on the Spitfire or left a light on the battery will be good because of your use of the car.

I'm 60 BTW and used to used my classics as dailes, for work, commuting to work, holidays, tours and club events so we're probably on similar lines of thought. Provided you have a relevant copy of the the good book (Driver's Handbook) for each of your cars and have read and refer to it, a must have.
Nigel Atkins

First thing I do if I'd isnt with the car is buy a copy of the drivers handbook which has a lot of good information about looking after the car spitfire is old school apart from electronic ignition but you would agree that is a good thing to have 😉
PW Creswell

Oh yes, I've no time for farting about with CB points, having a fully electronic (123) dissy my ignition is double the electronic compared with most.

I also don't believe in the misconception of maintenance being all about engine oil change and continuous carb fiddling (which is ironic as that just what I've recently been doing). Both are low priorities and after brakes, tyres, steering, suspension, lights/horn, and windows.

I also don't stick with only traditional oils and only bimbling around in classics or parking a shined car on grass for the afternoon - but it's all each to their own.

Piss-poor modern parts quality and poor quality people in the car trade are the biggest bugbears of trying to run a classic as a daily for me, which is why I bugger up the work for myself now rather than pay someone else to do it, cheaper and just about as effective.
Nigel Atkins

Couldn't agree more Nigel both my classics are for driving not displaying they might not win any prizes for being shiny and pristine.but they also dont sit for months in a garage not being driven.
PW Creswell

I was once asked to help pick contenders for car of the show by our club, 6-800 vehicles there, they never asked me again.

One year I saw the Mk1 Cortina Estate I vaguely knew of that had a replacement 1500GT IIRC engine as the car was very well used by a male district nurse for his work visiting patients at their homes. It wasn't tatty but certainly looked used, that would have been a contender to me.

I think I ran daily classics for 20-25 years before I knew that much about them mechanically but the experience of ownership taught me a lot (if only I could remember much of it) so I understand the lower level stuff non-technical stuff that those newer to classics may want to know.

Paul Hunt, the other contributor here is very knowledgeable and has a an excellent and very comprehensive website it's always worth looking up. - http://www.mgb-stuff.org.uk/hammertext.htm

Paul is much more of a traditionalist and we sometimes differ in our beliefs and views but still cover a lot of common ground, and differences offer choice.

I wrote a load of notes from helping a youngster new to classics cars, they're basic and non-technical but have helped a (very) few and you're welcome to them if you want, my simple but thorough (non-original) cooling/heating system cleaning notes have even, once, perhaps twice, been praised on the Midget and Sprite section here.

I've also saved some other useful notes or lists from other sources.

If you want any just email me (see top of post for address).

Nigel Atkins

Thank you Nigel I may have to take you up on that offer though I'm hoping the mg and spitfire will give me a few months weeks ok days then 🤣 of trouble free motoring
PW Creswell

Paul,
I'm across near Edinburgh if you need a hand or want to pay a mobile mech who also own's a few B's ;o)

You really need to get the meter out to see where the volt drop is in the circuit. You need clean connections all through the system e.g. battery, main cable on the starter, earth strap between engine and body (should be near the N/S engine mount), body to battery and solenoid feed.

Are you running the standard 2 off 6v's or a single 12v battery?

My guess is the body to battery -ve terminal... but its just a guess ;o)

11.6v on the battery is not great but the voltage when cranking is more important. Anything less than 10v and you'll be in trouble.

Best of...
MGmike
M McAndrew

Just an update on this issue looking at the fuse box iam right in thinking that the third fuse down is the ignition one if yes then odd thing it has a length of wire wrapped around it any reason for this and could this be part of the current problems iam having in getting the car to start just incase
PW Creswell

Whereabouts in Strathclyde are you Paul? I'm just starting the rebuild of a 1971 roadster and have many years experience of playing with MGBs. I'm in Troon.

You mention the fuses. The ignition and starter circuits are not fused. If you go to http://www.advanceautowire.com/schematics.htm you can download easily understood coloured wiring diagrams for all models of the MGB. The 1970-71 car is on page 7. Well it is on my copy!
Mike Howlett

Hello mike I'm in Glasgow roadster nice seen one last year driving past the hospital a 1967 really cool looking car yeah I think the wiring is a bit of a mess and needs looking at for sure 🤣
PW Creswell

"the third fuse down is the ignition one if yes then odd thing it has a length of wire wrapped around it any reason for this"

Wire wrapped around a fuse is a dangerous (temporary) repair for a blown fuse... get the wire out and get a new fuse of the correct rating. If it blows again you have another problem to deal with!

As Mike H says, the ignition circuit is not fused which in itself can be dangerous if the wiring gets damaged in anyway. Thankfully there seems to be very few instances of wiring related fires!

best of...
MGmike
M McAndrew

Wrapping wire round a fuse is really naff. For a start there should be two spares in the lid, but it wouldn't surprise me if there is a partial short on the green circuit somewhere blowing the standard fuses so they have beefed it up with wire - like putting a six-inch nail in your house fuse box.

Both my cars and several I have worked on came to me having had the fuel pump go short-circuit damaging the white circuit in the rear and main harnesses. Another not uncommon cause is the 77 and later overdrive switch on the gearlever which also has unfused wires, which chafe from the continual movement of the lever.

For that reason I always recommend fusing both circuits, even on the earlier cars with the column stalk and dash switches for the OD.

The easiest place for the pump is to use an in-line fuse with bullets where the white wire from the rear harness joins the main harness by the RHD pedal box. Similarly for the OD on earlier cars where the yellow/red in the gearbox harness joins the yellow in the main harness, but for 77 and later it's the white wire in both, using the same 4-way bullet connector as the fuel pump.
paulh4

That all sounds like double dutch to me Paul but I will have a look tomorrow as iam off for the day first thing is to check all fuses clean up the connections on the fuse box and refit them I have spare fuses next clean up and dirt or rust if any on the battery connections then no idea Trail and error 😉
PW Creswell

Paul,
email me I have very simple and straightforward info on fuses that may assist you.

The relevant good book will tell you which fuses do what and their order and numbering in the fuse box - but of course that doesn't allow for previous owners messing around with things.

Now what follows don't get too concerned about as it's easy (otherwise I couldn't do it) and some of it may not apply to your car.

I'd suggest you disconnect your battery fully (earth side first) charge up/condition the battery whilst its off and remove your fusebox and check it underneath too for crud any stuff leaked under it and that it isn't fitted upside down as can happen.

Take notes or photos of everything before and as you go along disconnecting items and compare against the good book as if a PO has wired things differently it might not be straightforward to just reconnect as per book.

Trial and error will only get you so far, a more methodical approach will be quicker, more effective and perhaps cause less additional repair work or unnecessary replacement of parts (especially as many modern made parts are so piss-poor and original parts often very serviceable) - but I'm very happy to replace new for old if it brings improvements or saves me time or effort.

BTW my notes are more about maintenance prevention than repair, better to prevent as roadside repairs are only for those that seem to love that sort of ownership.
Nigel Atkins

"That all sounds like double dutch to me Paul"
Lol, you have a lot to learn young Padawan 😂

Best of...
Sounds like you might need it!

MGmike


M McAndrew

@ M McAndrew you said you know a mobile mechanic I may need his assistance as I feel I have looked at the wires and looks like a bowl of spaghetti problem is the car was repainted and the guy who painted the car during a blackout had lots of over spray all over the fuse box and wires so basically they all look red now lol .also ordered a new battery the battery isnt taking a charge but it's been lying for nearly two years I cant expect it to be in perfect condition. So new battery will be with me on Thursday I'm off work till Monday at least so hope to try and get it sorted but if you can send me the mechanics number would help me out thanks guys regards Paul
PW Creswell

Paul,
if you can put up photos (two per post) we might be able to help you and you may be able to do more than you think as most of the wiring is quite straightforward. Of course this doesn't allow for gross incompetence of previous owners that can do so strange things that can't often be thought of.

You can't do much until you get your new battery anyway, but you can take photos.

Do check when you get your new battery that it is actually fully charged, they usually are but I've had one that wasn't fully charged.

Good luck.
Nigel Atkins

Yeah I will put up photos and see what you guys think I'm sure it's a simple thing and I'm just over thinking things I do have one photo for now not sure it helps but will take some tomorrow before I head off to work on the right of picture the silver box is that the ignition relay?

PW Creswell

Ye Gods, what eejit did that? All that overspray on the wiring certainly makes diagnosis more difficult. Cellulose thinners on a rag should clean up the colours. However, it looks reasonably standard. The power comes in on the left and leaves the fuses on the right.

The top two fuses are for the front side lights (top fuse) and tail/number plate lights (second fuse). The left side of these fuses are connected together and the input from the light switch is red/green. All four outputs are plain red.

The third fuse is for ignition controlled circuits and has a white input from the ignition switch. All the outputs are green and power brake lights, reverse lights, gauges, heater fan, indicators, wiper, and heated rear window.

The bottom fuse is live all the time and has two brown wires on the left side. One is the power coming in from the battery/alternator and the other is feeding the starter relay, which is the silver can next to the fuse box. Purple wires leave the right side of the fuse and feed the horns, interior lights, and headlamp flash switch.

The only components involved in operating the starter are the battery and its cables, the engine earth strap, the ignition switch, the starter relay, the motor solenoid, and the starter motor itself.

The third fuse is only for the things I mentioned above and would have no effect on the starter operation.

Common problems will be lack of volts at the motor, usually caused by dirty connections and/or inadequate earthing. If the starter works at all I would assume that the ignition switch and starter relay are operating properly. My first job in your situation would be to dismantle and clean all the connections from the battery posts to the starter and solenoid, and to check and clean the battery earth cable and and the engine earth cable.

There's no substitute for going through it methodically checking everything as you go. A cheap volt meter would be useful to find out how much voltage drop you get when the operate the starter. Were it not for Covid I would offer to bimble up to Glasgow and lend a hand. Good luck.
Mike Howlett

Couple of more pictures looking at the wiring I can clearly see three wires just hanging two coming from wires going to the alternator so again have they been replaced and are now redundant no idea perhaps some of you guys can let me know think I need to clean off the paint on the end of the connectors going to fuses pretty sure paint isnt a good conductor




PW Creswell

Thanks mike for the information yeah this bloody covid is causing no end of problems see it everyday in work again thanks for the help have a few days off so they and get this sorted on Thursday and Friday new battery should arrive tomorrow fingers crossed
PW Creswell

That's a mess, and I don't just mean the paint.

Two Scotchlok connectors in the feed for the parking lights, and after-market bullet forced into standard connectors doesn't bode well.

Under the circumstances those wires could be anything or nothing, the thing to do is find out what doesn't work and take it from there.

I don't think we know what the actual problem is yet other than that it won't start.

You said there is a whirring noise, where is that coming from? Is the engine turning over? Or is it more like a chattering from the starter?

The starter whirring without turning over the engine shouldn't happen with the pre-engaged starter unless the starter is faulty, or maybe a badly damaged ring gear, and it seems to have been doing it with both the original and a replacement.

Connect a voltmeter between that battery cable stud on the starter body and the starter body, note the voltage, then turn the key to crank and not the voltage, and whether the engine turned over or not.
paulh4

Unfortunately need to wait till Thursday before I can go out and and try to start car but sure when I did before there was a power drop when I turned key to start the car like I tried it at night and the dash lights dimmed each time but the connectors on battery terminals need a clean the earth wire to car looks ok but is a little dirty so again clean that before connecting new battery checked voltage is ok then try and start car and check voltage as I do that see if it drops or not easier thing to do would take it to an auto mechanic and get a new wiring loom but that would be very expensive I'm sure and a lot if worked as well
PW Creswell

ETA: you both posted whilst I was still typing (this happens a lot with me)

Yes, well, er, uhmm.

Generalisations from me, the wiring and often (original) connectors on these cars, same as many mechanical bits, tend to be very tolerant of less than high standards of work with them. This is why bodgers and owners that keep them at a low standard of service, maintenance, repair and running can keep the cars going, some not realising how much under standard they are and how well they could or should run.

With the wiring in the first photo four things that immediately assault my eyes are -
. the mix of blue and red crimp connectors on what appears to be the same gauge of wires - red is for thinner wires than blue (though both can be used on 1.5mm)
. modern bullet connectors going into original style bullet connectors
. the Scotch snap connectors (to me horrible things) are often used to tee one wire into another which if there's a lot of them can sometimes suggest an alarm or immobiliser was once fitted and then removed - or it could just be someone had a lot of them
. two so close together on the red/green wire.

Also the blue fuse is a modern often now supplied, slightly different size (and probably 35amp) as per note sent.

It's a good idea to turn all fuses in the box so that you can instantly see if they're blown.

Looking at the other two photos some of the the modern blue and red connectors *look* to be crimped reasonably or well which doesn't tie in with the other work, suggesting perhaps different people's work, at perhaps different times.

I never like to see an odd HT lead even if it is the king (coil) lead, why has just one been replaced(?).

I don't have a wiring diagram so I'll not comment at all on the unconnected wire - plus Paul Hunt and others are experts in the electrics.

What I will do later is send you some info on tools you'd be wise to invest in, and if I can find them details of better quality (by modern standards) crimp connectors.

Unfortunately I suspected something like this might be the case, as it often is I'm afraid, but it can be sorted and as long as it's safe and working tolerated for a while whilst you replace as required.
Nigel Atkins

The HTC lead was me I'm guilty the original one was all full of white gunk had a spare one lying around brand new never used so thought might change it over cant hurt will ofcourse order a full set of matching ones
PW Creswell

Tou know from the outside car looks great lol

PW Creswell

The voltage will always drop when you turn the key to crank, but by how much and what is happening at the time is what is important.

A good system should still have 10v when the engine is cranking.

As the battery weakens and/or the connections worsen the voltage will drop further and the engine crank slower, and eventually all you may get is the solenoid chattering.

Whilst powering the motor will cause the biggest drop the solenoid also causes a drop, even when it isn't powering the motor, especially if it is left with the high-current pull-in winding powered for some reason instead of switching down to the lower current hold-in.
paulh4

Know more on Thursday hopefully get it started on the plus side hot a back seat in leather ones in car are cloth not the worst condition but not that good either but if anyone looking for a set of back seats let me know will take a picture when out of the car ok
PW Creswell

As you say, nice looking car. But the wiring is a mess. It's impossible to say much more except to mention that any car-person worth his salt will never use Scotchlock connectors - and you've got a few! As for those "spare" wires - who knows why they are there. The wiring on my '71 roadster looks a bit similar (without the connectors or overspray) but as I'm doing a full rebuild I shall use a new wiring harness.

You said you are a hospital worker. What is your role there, and in which hospital? I only ask because I spent 42 years in hospital labs, 28 of them in Ayrshire and Arran, and the first 14 in Surrey. I have visited most of the Glasgow hospitals in my line of my work.
Mike Howlett

Oh I'm just a porter nothing fancy
PW Creswell

Porters may not be fancy but they are absolutely essential for the smooth functioning of hospitals. Don't belittle your role. All the porters in the various hospitals I worked in were the salt of the earth and a great bunch of guys (and a few girls). We had no less than five permanently working for the labs in Ayrshire.
Mike Howlett

Paul,
if you fitted the coil lead that's OK as you know why and the provenance of it and hopefully that it's good quality and condition.

One of our neighbour's is a porter at our local general and he is one of only two people (and his wife) we know that have had confirmed Covid. The other is a friend of my wife's, and works at the local general hospital. She didn't even know she had it until the test.

Whereas our neighbour was initially off work for weeks, he told me at one point his wife called an ambulance and they told him he had Covid-anxiety because of his breathing problem. As I pointed out to him it was only natural to be anxious about not being able to breathe, it's like drowning, which is why some use it as a form of torture or means of getting evidence (by torture). Months later he still has breathing issues and is so anxious now that it's only last week he was able to meet his boss to discuss his return to work but he was only able to be in the car park and not in the building yet.

The majority of the general public would have no real concept of what it's like in medical places for the staff dealing with Covid and the increased potential to catch it, and only now learning of the effects of Long-Covid.

You could say you're only an (obscenely overpaid) sportsman or media star - but not *only* a hospital porter.
Nigel Atkins

Update got new battery checked it was charged checked all cables to battery had no dirt or rust all nice and tight fuse box all clean and no obvious fraid wires going to starter motor and it is just spinning .so when old stater taken out it was two bolts no washers or shims same size of motor back on but could it be that this motor may require a shim ? I know old the spitfire it does but that is not a pre engaged stater and checking g on rimmer bros it doesnt show and shim for motor so I'm at a lost here .as Dirty Harry once said mans got to know his limitations
PW Creswell

If the starter is spinning, but no engagement to the flywheel, it would seem the bendix drive has failed. Replace the starter

Cheers

Gary

79 MGB
Gary Hansen

It's a brand new stater
PW Creswell

Can you take it out, run it on the bench and see if the bendix works?

Jud
J K Chapin

I dont have proper tools to do that and I dont fancy having to get a mechanic back out unless I was sure the car would then start need to try and hook up jump leads and see if it is a problem with starter but again not sure if I can do that as again starter is right under car
PW Creswell

Hi Paul,
sorry I missed a few updates...
I was referring to myself as the mobile mech lol

If you don't get it started today send me an email with your contact details and I'll load the car up with tools. I can shoot over tomorrow in between fixing a Citroen and going to have a look at another ZB project!

Best of...
MGmike
M McAndrew

helps if I unhide my email!
or
call/text 07831 808321
M McAndrew

Just because the starter is "new" doesn't mean it works. BTDT

Cheers

Gary
79 MGB
Gary Hansen

Gary and Jud speak of the Bendix not working, but the '71 MGB has a pre-engaged starter, so there is no Bendix. Could it be that the solenoid isn't pulling the gear into mesh with the flywheel ring gear?

If Mike McA can get over to help, grab the offer with both hands - don't forget your face mask though!
Mike Howlett

Well Paul with a new fully charged battery you are actually starting (pun) from a good place. Be interesting to see what Mike finds.

Gary makes a good point about don't assume because something is new that's it's the correct item or fully functioning, same for existing parts.

Mike,
when are you next Northampton way, I've always multiple MG problems and issues I need help sorting, sunny and warm here too.




:)
Nigel Atkins

If the motor is spinning then it's fairly certain that the solenoid is moving what should be holding the pinion as that is part of the mechanism to close the contacts to power the motor.

As both old and new starters seem to me doing the same thing then it has to be time to check the ring-gear as mentioned some time ago. But before that, as running engines usually stop in one of two positions, it's those positions on the flywheel ring gear that wear the most. So put the car into 4th gear and nudge it along so the engine makes about a quarter turn, and try cranking then. If it cranks the engine then the ring-gear has to be considered highly suspect.

If it still doesn't work then it's starter out time and inspect the operation - fore and aft and rotational - of the pinion when the starter is powered. This will need 12v on both the battery cable stud and the solenoid operate terminal. Also inspect the ring gear as best you can i.e. that it is still attached to the flywheel!

It's also possible you may have been supplied the wrong starter for your engine. There are pinions with different numbers of teeth for the MGB, as well as quite posibly different dimensional requirements for other vehicles.
paulh4

AS usual Paul makes some good points. Of course the solenoid must be pulling in or there would be no electrical contact - I should have remembered that. As for the number of teeth on the pinion, I had that trouble with the Elan I once owned when I fitted a non-standard starter motor.
Mike Howlett

Update time car is running turns out old starter is kaput and new one the mechanic put a wire in the wrong place it was as simple as that just shows you even people who are trained can make simple mistakes as well so no on to the fun stuff like sorting out rear lights and fuel gauge
PW Creswell

I didn't make it over today but was going tomorrow until another kind soul dropped in to fix it. I'll let Paul tell the tail when he's next on because I'm not sure of the details. oh he has while I've been typing!

Nigel,
always happy to help but in this strange world and time we live in I've not ventured south of the boarder for six months!!!! I'll be losing my Geordie accent if I don't get home soon for a top-up.

Paul,
I was in the same place as you re the ring gear and suggested the very same test!

Best of...
MGmike
M McAndrew

Failure on the mechanics part to test work at completion?

We all make mistakes but no doubt you had a male mobile mechanic and it's against their ego to read the installation instructions, same for other male tradesmen.

To be fair Paul had it at his first post, and Gary with just because it's new (installation in this instance). And for myself 'Problem solving notes' only because it's happened to me so many times.
Nigel Atkins

Mike,
same has happened to me, but it happens often to me as I type so slow, others post whilst I'm typing.

I'll still have plenty of work for you no matter how long you're not allowed in.

Chers.
Nigel Atkins

Paul C. Glad you got to the bottom of the problem finally. On to the next issue. There's always something that needs attention.
Mike Howlett

I realise it's not going to happen, but I'm really intrigued as to just what the mistake was. Assuming he got the battery cable on the stud (!) there is only one other wire on a 71 and that's the solenoid operate wire. Even if it is the 18V starter with the extra unused spade on a 71, connecting the solenoid wire to that would mean the starter would do nothing when you turned the key to crank.

The only thing I can think of is that he had connected the solenoid operate wire direct to the motor, somehow!
paulh4

I have no idea I could ask Mick the guy who noticed the mistake I was under the car cause thought take out the starter but then he said let me have a look before we unbolt it and he said mmmm think this wire is wrong and he moved it .Anyway all lights now working horn radio but need to look at the fuel gauge and when wipers they were working then stopped but you can see the wipers have slight movement and can hear motor so question could this just be sticking due to dirt or grease or could it be spindles and are the wipers easy to take out sorry to keep asking questions but I guess that's how we learn
PW Creswell

I'd have a look at it with Mick there if possible.

I can't remember much about Bs, there's loads of info on Paul's site, the Driver's Handbook for (factory) wiring - and your senses, eyes, ears, nose and touch.

I'd normally first look at the wiring but with your car's wiring instead first I'd remove the wiper arms to reduce the stress on the system and motor and see if that improves the the speed the spindles(?) move at, add a few drops of 3-in-One oil, even if it doesn't change things it should help anyway.

The speed up if it happens could still be drive mechanism or motor or wiring.

Whilst removed check the wiper arms, blades and rubber elements aren't loose from wear or stiff from age, muck, rust(?), clean and lubricate the arm, clean the rubber blades.

If OK to do so I'd then put the arms back on and try the wiper first off the screen to check then on the screen wiping dry and then wiping with spraying water on the screen. Any differences in the speed only tells you the extent of the issue.

I'd clean off any old grease (probably with fluff/crud/muck) on any part of the drive mechanism and add a little fresh grease with a cheap artist paint brush.

Check and clean the connections and wiring to the motor and switch, all should be clean, secure and protected. Note/photo all wire colouring and connection position before you remove them, you could check them against the factory wiring diagram and let us know of any variations.

If during any time you smell electrical burning, you'll know as it's quite distinctive, stop.

With the wiper motor going you could feel if it gets warm - always be careful or touch anything on these cars as there could be potential for you could to get burnt, electrocuted, scalded, cut, graised, splitters, you probably seen these people at your place of work.

I'm sure others will be along with better ideas.

Nigel Atkins

Is the motor whirring but not moving the wipers :o)

I partially jest, but the drive rack can break and that's exactly what happens.

Could be low voltage due to bad connections or binding wheel boxes. You can get an idea about the latter by lifting the blades off the glass and moving each arm in turn back and fore. There will always be some lost motion (free play) in this rack and pinion system so how easy each arm moves, and if it starts to move the other one, will give a clue as to how free they are.

If they seem free, and the motor is NOT whirring, then it's more likely to be electrical. If the heater fan slows (if it works!) when turning on the wipers it could be a corroded fuse or fusebox connections. For the 1970 model year this was the 2nd fuse up in the fusebox, but for the 71 model year there was a separate in-line fuse under the fusebox.
paulh4

PaulC,
as PaulH posted I was unable to correct my typos and sentences order in my previous post but I think you'd get the general idea, one thing I was to alter was greasing the rack I meant at any points, if any, that you can reasonably easily get at.

I was also going to suggest that, if you want to, you put up your 'Vehicle profile' and make it viewable on the threads and posts as that can sometimes help with giving answers (for those that look at your 'Vehicle profile') and save you sometimes having to remember to always say.

Click on the 'View vehicle profile' on my posts to get the idea.

Nigel Atkins

PaulC,
I've just realised I've not suggested this to you - to eliminate the wiring, switches and connections (except those on the item of course) and poor earths I use a direct supply from a/the battery positive and earth posts to the item (stand back if it's a horn).

Obviously all the usual safety precautions and procedures should be observed (sparks and fumes).

I've got a length of twin lead off a broken household appliance long enough to go from my car battery to any point on the car. Both ends have fully insulated spade connectors. For the battery I use battery post clips, for the item end I've made up various tail connectors for item connections and earths.

It also allows for the item to be tested on the car so it can do whatever it's job is for testing and saves removing the item. You can get testing probes that do the same and a lot more but the homemade lead testing sets are very cheap and easy to make and use.

You could also use the lead and various connection tails for going to or from switches, connections and items to eliminate various sections of wires and connections, ect..
Nigel Atkins

Another fuse separate from the main fuse box is that from 71 onwards cause I dont see another fuse only four in the fuse box.dont think it can be a wiring issue as the motor is working and I do have movement all be it limited the wipers are jerking slightly if I move them with my hand they do move a full rotation then stop and both move together like they should so this is why I was thinking maybe just stuck with dirt etc problem here is how to you get to the mechanism. Do you take off the heater then plate behind heater or is access through dash ?
PW Creswell

No, behind the dash on the driver side.

Remove the U-clamp, the six screws holding the lid on, then the circlip holding the crank pin on the big wheel. With the crank out you can lift the rack out of the end of the gearbox casing, unplug the motor to remove the motor.

You can then push and pull the rack by hand to see if that's stiff, but really you can check that with the arms as I said earlier.

To check the electrical circuit everything needs to be connected back up, and the motor powered and running slowly, to be able to check the voltage. If you don't do that and test the wiring disconnected from the motor, or the motor disconnected from the rack, it's not a fair test.

And at the very least the screen should be wet when trying the wipers, dry is not a fair test either.
paulh4

Yes I should have added clean and polish the screen as well as clean (and polish) the wiper blade rubbers (called elements). You can use something like Autoglym Car Glass Polish on the screen and blade rubbers.

Normally you'd never want to use the wipers on a dry screen as I put in my notes but this is a test situation and handling the wipers whilst they're on could also introduce the same level of further stress, but additional stress can highlight 'flat spots' in the wipers action perhaps narrowing down the area of resistance/wear.

I'd turn the ignition off at points of judder and record these points to see if there's a pattern and/or particular area or a more random overall looseness/ wear.

In-line fuses can be tucked out of sight sometimes but I don't know about Bs so Paul will advise.

Getting the heater out and back in can be 'fun' so best left until you are prepared for it and as with many jobs on the car you might not discover what wants changing or refurbing until yo actually do the work.
Nigel Atkins

So in order to see if maybe something is stuck or to even clean things up need to take out the whole dash sounds like a big job seen things like that on wheeler dealers lol not sure I want to end with a lap full of wires .so the u clamp and screws I'm in right in thinking this is after i remove the dash to get access to the wiper mechanism and motor .
PW Creswell

I didn't say to remove the dash!

It's behind it, and unless someone has put a cover under it - which should be removable anyway, kneeling on the ground by the door and looking up behind the dash should reveal all.

If they move with help that doesn't really tell you anything by itself, it could still be stiff wiper boxes or poor electrical connections as said earlier.
paulh4

No, if you crouch down and look under the dash on the driver's side of the car you will clearly see the wiper motor held to the bulkhead by the U-clamp with two bolts. Undo the two bolts and remove the U-clamp and the motor will hang on the rack. The mechanism is hidden under the shaped flat plate held with tiny bolts. Find a small enough spanner and remove the tiny bolts, then the plate comes off.

As Paul H described you will find a large greasy wheel linked to the rack with a connecting rod. Undo the circlip that fixes the rod to the wheel and lift it off. Now the motor is free, so unplug the wiring plug and you have it in your hand.

Now you can try pushing and pulling the end of the rack to see if the wipers move across the screen.

All this work is done kneeling on the ground and leaning inside the open driver's door. It's not easy, but it is possible - I've just done it last week! See photo taken during the build of my V8.


Mike Howlett

Ahhh got ya ok well I have knee pads so that will help 🤣
PW Creswell

So just take out motor and the silver plate beside it in picture is where the gear is take that off and I should be able to see if anything is stuck or broken

PW Creswell

Yep. The circular bit of the plate covers the large plastic gear wheel. Where the plate goes up to the top left of your photo is where the crank and end of the rack are housed. The motor and the drive gear etc are all one piece.

More overspray I see, and some non-standard electrical connectors too.
Mike Howlett

Yes the plate will come off the wiper motor DO take a photo and note the position of the gear arm when it's parked and where the rack is because if you fit it wrong the wipers will clean your bonnet, guess how I know.

Check with others but I've got a feeling you can run an view the motor, gear and rack operating with the cover off - but do check before doing so in case I'm wrong.

ETA: more modern bullet connectors and they look poorly crimped, check these before anything else just in case this is all your problem is (now you're seeing why I like the direct connection to item from battery to bypass these type of connections to check item itself).


Nigel Atkins

If you run the motor with the cover off things could start jumping out of the casting so you would have to press them down firmly while it is moving, and I'm not sure how much it would help anyway.

Watch out for the thin shim on the crank pin under the con rod, and for the circlip pinging off of course.

With the con-rod removed you can lift the end of the rack tuning and the rack out of the motor case to be able to test the two parts individually i.e. the rack gear for how much effort is needed to move it, and the motor for how fast it spins. But of course without the load of the rack etc. the motor is always spin to spin faster, even if the problem is bad connections resulting in low voltage at the motor. The only way you will determine that is by measuring the voltage right on the connector block terminations while the motor is driving the wipers on a wet screen.

Sweeping your bonnet will only happen if you have removed the arms, then refitted them with the motor having been moved to a different position. To avoid that don't refit the arms until you can turn the wipers on and off and see the spindles rotate then come back again and the motor stop, a couple of times at least.
paulh4

I was thinking of the wiper arms being removed and fully inspected and attended to as required. As the car is new to Paul I think it's best to not only solve the problem that's presented but also whilst doing so go through the system/circuit/component to check/adjust/amend/repair/replace all items as required so that you know that's one system dealt with or at least you know what needs further attention later.

Yes, mark and record position of all parts and components before you start work and then check and check again what you've already checked before starting testing, and test before fully operating.

I'm afraid with me it's a case of "do as I say not as I do" - but you can learn from my many, many mistakes and all of my very expensive experiences of overall ownership, often easier and less expensive to learn from the mistakes of others, and I can claim some expertise in this area of mistakes and experiences (unfortunately)!
Nigel Atkins

Shipwright's disease.
paulh4

I had to look that up Shipwright's disease and second listing was PaulH's site.

I disagree, if the car is just about totally unknown to you, and particularly when there's so much evidence of potential PO bodges I think it's at least worth checking, and repairing then, or know about it for later.

Just so the PaulC and other readers that don't already know are aware - I can absolutely assure anyone I don't look for any extra work on the car, I loatheeee, no I mean really loathe, working on the car, I only enjoy driving it. I'm not like almost all on here I think the cars are for driving not farting about with.

I'm not suggesting going to too much trouble now, do what's easy to get at for now, I wouldn't be taking the rack out for now just doing as usual clean and lubricate (where you can).

I do believe in dealing with safety items, like the windscreen wipers, ASAP, things like fiddling with engines, carbs, gearbox are lowest priority items.

I'd be doing a full 36k-mile service and check but staggered in between driving the car. I'd certainly not take the car off the road for winter to do a partial restoration.

Prevention is better than cure, doing the jobs in your own time at where ever you keep the car is far better than being a roadside repair hero, I've had enough roadside sortings to last me two lifetimes.

Get the wipers working reasonably well and as required add other work on them to the to-do and roundtoit lists whilst you get on with driving the car and going through the staggered 36k-mile service and of course all the other maintenance, and PO bodge sorting and unexpected distress repairs and replacements.
Nigel Atkins

"add other work on them to the to-do and roundtoit lists whilst you get on with driving the car"

That's all I'm saying. Learn about your car by driving it.
paulh4

We agree, again !?!

But you do have to have all safety items working reasonably and reliably, not just working for now and then unsure for regular short and medium term use.

I'm for prevention, particularly of the car needing roadside attention - and not starting. If you can't start the car to use it that's a pain but not being able to start it to diagnosis, or by far worse still not being able to start it to drive it home is a complete no-no in my view.

I'd always sooner get the car home, without roadside repairs if possible, even if it caused a bit more additional work by doing so. That's one of the advantages of having these overpriced old-bangers called 'classics' rather than a modern, to be able to limp the car home, to where you're going or somewhere convenient, rather than be stranded.

I used to be quite precious about my over-priced old bangers and their mechanicals but the vehicles and the motor trade wore me down and since Midget ownership I've completed weekend tours and drive outs with faults or limping home in some way and just 'turned the radio up' (although I don't have one in the Midget).

Nigel Atkins

I agree that safety is a major factor with me I dont drive my cars if I have anything wrong with them sort it out then drive them dodgy paint work or a torn headliner is last on the list so hopefully weather is ok tomorrow so I can try and sort out wipers
PW Creswell

Quick update I now realise I'm old lol that was bloody painful trying to get to the wiper motor anyway got the motor off disconnected power took lid off gear box everything seems to be in order nothing looked broken etc wet windscreen and wipers moved freely back and forth with no binding or sticking so guess it's down to faulty motor maybe worn bushes or bad connectors
PW Creswell

Brushes can be replaced, but having done both of mine they were more a case of reluctant to start, and switching to the faster speed they ran as they should. The comms were unworn, so I'd suspect electrical connections.

See if the reverse lights or brake lights dim down when turning the wipers on, if so it's probably the fusebox or its connections.

Otherwise put voltmeter probes in the connector block and see what voltage you've got when the motor is driving the blades across a wet screen. Should look like the attached, 12v on the red/light-green for slow, and blue/light-green for fast. Green and brown/light-green are used for parking via the manual switch when it is off, and black earth is used with all of them.


paulh4

Ok will check that out when I get back from shopping that's the problem when I'm not working house husband lol
PW Creswell

PaulC,
don't forget to test the testing equipment before carrying out each test (especially if you have a cheap modern digital multimeter). Test it on (a 12v) battery posts, especially if it's not the Bs battery as you're using it, the readings should be consistent (Spitfire or spare 12v battery).

I think the fusebox has already been checked but never hurts to recheck.

Often helps to have a second pair of hands, eyes and ears (and nose) with you whilst doing stuff like this as they can perhaps see, hear, smell stuff you can't at the time of having your head stuck elsewhere. Also to wiggle wires and connectors which can often highlight a hidden poor connection(s).

Also, not now but for the next issue/problem it often helps to bring in those that know the subject (and I'm certainly not discounting the other posters here) to start a new thread with an appropriate title to it. I very often run other subjects into a thread or just complete tangent drift, so do others, which is fine but not always the most effective way to resolve other issues.

If you think you might get into and enjoy(?!) sorting the electrics it'd probably pay you to buy (or borrow?) a testing probe, something like, see attached PDF.
Nigel Atkins

I don't enjoy messing with electrics but it seems most old cars do have a multitude of problems mostly with bad connections so at £19.99 for one on ebay it would be worth having I take it with a probe it is a lot easier to tell if you have a bad connection .and typical of Scotland it's raining but hopefully be dry after dinner so I can go out and check if lights dim any when wiper motor goes on
PW Creswell

According to the official workshop manual, the wire shown in green in Paul H's photo should be green/pink. I suspect the pink tracer just doesn't show in the picture. I haven't checked my own cars to see what they have.
Mike Howlett

Having checked lights non go dimmer when wiper motor is on .I did notice something the rod sticks out from the gear box is it suppose to cause I'm thinking it shouldn't and if I'm correct then it looks like the whole thing needs to come out hopefully I'm wrong
PW Creswell

"the rod sticks out from the gear box"

Not sure what you mean.
Mike Howlett

Depends on what you mean by rod, the exposed spiral rack, the outer tubing that covers the spiral rack or note in the photo I put up the ferrule that an over nut (union) should screw to that buts the outer tubing to the ferrule and motor arm end.

Not all classics are full of badly deteriorated wires and connection or badly made or corroded but there's usually a few that crop up. The probe is very useful but not the be all and end all but very good for testing new parts before fitting or new parts recently fitted and testing items without removing them, and finding poor earths. A step up from my wire kit and test bulb and with more functions and convenience but the more skilled in electric I bet prefer a good quality multimeter.

A test probe is very good for finding quick yes/no and working back or forward on a circuit looking for more yes/no but perhaps not the greatest diagnostic tool for the more knowledgeable.

I think with practiced use of it and using it with others tools like recording instruments (phots/notes/drawings, thinking, asking questions) it'd probably serve you very well.

I've no idea if £20 gets you a reasonably good and reliable version but I do know faulty or unreliable test instruments (or tester) can caused a lot of unnecessary time wasting, costs and frustrations.
Nigel Atkins

The spiral part part of it is sticking out from the sliver gear box I'm not sure it should I can also see a grey plastic part is this suppose to secured to inside of gear box having opened up the gear box I could see the spiral part was connected to the long metal part which then connects to the centre gear so that seems correct and there is a plastic part right on the pointed end of gear box and that seems correct as well
PW Creswell

I can't remember how to snip, paste and present the image here so have a look at this page for the illustration (ALWAYS check any information from any source, Toss make errors and repeat errors) and see if you have part number 13, "TUBE, outer, (motor to w/box)" adrift or missing from your set up.
http://www.moss-europe.co.uk/shop-by-model/mg/mgb-c-v8/electrical/wipers-washers/windscreen-wiper-system-mgb-mgb-gt-1967-80.html
Nigel Atkins

I found this photo of what the business end should look like. The crank arm is on the right and is in the fully extended, parking position. You can see that the spiral rack is completely enclosed within the rack tube and the neck of the motor. With the cover plate on all you should see is the large nut with the rack tube coming our of it.

Mike Howlett

Wow a vintage photo from the days when TV guides were paper printed, a classic!!

Just joking, well done Mike great photo and post, just what was really needed.

When I done my wiper gear and rack I had the start of a cold, well full blown man-flu really, and my thinking was, if you can imagine it, even worse than normal and the posters to my pleading thread just couldn't see or follow how I'd got so much ar*e-about-face and neither could I. Luckily the miracle of a few Lemsips and couple of days later I was in the top percentile of Mensa UK.







And felt 20 years younger ;)
Nigel Atkins

So question now is how do I get the spiral bit back or the plastic part to cover it without resorting to taking everything off the car which I would rather avoid if possible
PW Creswell

The wires to the wiper motor and (heater fan switch) are only green/pink when there is the auxiliary fuse on the 'accessories' circuit under the fusebox which Paul has said he doesn't have.

It's normal for the rack to protrude from the short tube on the passenger side wheel box. Why they didn't make it a bit longer, or lever it out is one of those questions that will never be answered ... if that is what you mean.

But if you are talking about something at the motor end then I'm at a loss. Have you taken the connecting rod off to disconnect the large gear from the rack? I thought you had from "wet windscreen and wipers moved freely back and forth" and you were pushing and pulling on the rack by hand. If so the spiral-wound rack should just push back into the tube that is bolted to the end of the gearbox, and they should all be metal as Mike's picture shows.

But if you hadn't and the motor was moving the blades then there is nothing wrong with the mechanism - assuming the cover isn't distorted and jamming things up. Other than that it's probably electrical and removing the U-clamp has joggled the connector. Was it the motor that was driving the blades?

The only plastic bit I'm aware of is on the connection rod and goes over the crank pin on the large gear wheel.

You could really do with posting a photo of what you mean.


paulh4

I'm with Paul H in that I can't understand to what you are referring, particularly your reference to a plastic part. A picture speaks a thousand words.

Thanks for the explanation regarding the wire colour Paul H. Looking at the wiring diagrams 1970-71 was the era when they started fitting the in-line fuse and changed the wire colour. I must have a look at my 1971 car and see whether that has the fuse and G/K wire or not.

Nigel, I found that photo on a Lotus Elan website. I've no idea how old the picture is, but my wife and I still buy the good old "Radio Times" for our TV guide. Ye cannae whack it, as they say up here.
Mike Howlett

I'm the same as Paul (ETA: and now Mike) lost and suggest a photo - unless you mean part number 13, "TUBE, outer, (motor to w/box)" is adrift or missing from your set up but this tube is metal, unless yours has been replaced with some plastic tubing in which case this might contribute to or explain your current problem.

(ETA: Mike, I'm actually a radio listener but can't remember what radio station listings were in the Radio Times last time I saw a copy but I don't think it included even BBC World Service).

Nigel Atkins

See what I mean about the metal spiral has come out of the end of silver gear box so I gather in order to get it back I need to disconnect the long metal plate in the gear box that has a peg on one end that fits in the end of metal spiral and hopefully just push the spiral back till it's back in the tubing

PW Creswell

You just have to push the tube and the motor casing together and tighten the nut, i.e. push the spiral rack into the tube. I had one come loose in very heavy rain and the wipers got more and more reluctant to move, but knowing the system I reached under the dash and tightened the nut by hand as I was driving along and that was enough to get me home.

If you can't push the rack into the tube then either the wheel-boxes have seized, or maybe by now the rack has been bent and may need to be replaced. Although they have some flexibility they are pretty stiff, and if those bends are 'permanent' it's going to make moving the rack in the tube stiff as well as everything else. You _might_ be able to straighten it.

I've had to do replace one when the spiral part pulled out of the socket the connecting rod fits into, it was way too long so had to be cut down.
paulh4

No, the tube is flared at the nut end, this is pushed against the ferrule (the threaded bit sticking out of the arm of the wiper motor housing) the union nut is then screwed to the ferrule which holds all together.

The coil rack needs to be straightened to fit the tube properly and drive the wheel boxes (that turn and move the wiper arms) properly.

But - the thing is, why is there this gap between the tubing and motor, is the motor too far away or is the tubing too short, coil rack too long - you need to check the run of the tubing and rack and as they relate to the wheel boxes.

Just by your photo (aren't they useful) you can see why the operation of your wiper wouldn't be smooth.

Nigel Atkins

Once again someone posted whilst I was typing, I have to check spellings and words as my spellings are beyond what the onboard system.

Getting rid of that first exposed bend in the rack (coil) will help a lot but I'm not sure how the tube could have that much gap and it not push against the wheelbox on the driver's side. You certainly need to look at the full lengths of rack and (over) tubes.
Nigel Atkins

Well got it to go back in but when putting gear box back together bloody circlip went ping and spent an hour looking for it anyone know the size so I can try and get a new one typical you manage to hopefully sort out the issue and go through all the hassle only to lose a stupid little clip and that's it game over lol
PW Creswell

Sorry I don't know the size and no point guessing, Paul might know though.

This is the thing with these cars, some will tell you that you only need a basic tool kit to work on them, to me this is bollocks because to do a lot of jobs well and avoid breakages and losses of things like circlips you need circlip pliers and then a set of them for internal and external, and then you find you need angled nose, no the other angle, and on it goes.

I'm not even sure the one that goes there is a standard circlip, possibly its a hard to come-by special type.

Something I only started yesterday was using a magnet to hold, remove and replace a small washer, I'm going to try it on other things, obviously some places you can't or shouldn't use it.

A tool I've found many uses for, and as a fastener, is blutac (or whitetac), holds, moulds, spaces, temporary and permanent fixes too, holds my gear knob and rad grille badge inserts on, both for many years.

Blutac left for a period of time will hold a tremendous weight, many pounds.
Nigel Atkins

You need to find that circlip, 'cos it isn't really a circlip, more of a flat spring clip. It is shown in one of Paul H's photos a little way up the page. I have no idea if you can get one new, but there will be one in every scrap wiper motor :)
Mike Howlett

Did a bit of research correct it's not a circlip it's an e clip so will attempt to locate it tomorrow if not off to halfords
PW Creswell

I'm not sure if it's an e-clip as such but an e-clip or other type of clip or fastener with the correct requirements would surely do(?).

You'll also need that plain spacer(?)/thrust(?) washer too, hopefully you still have it.

This is obviously a slightly different motor and not all of it relates to your motor but it gives the general idea or the set up well and towards the end info on fitting a circlip. - http://www.youtube.com/watch?v=wGtUG1kUFn8
Nigel Atkins

If you Google eclip or circlip you should find loads of examples from the likes of RS Components, Euro Car Parts et al. 'Just' a case of accurately measuring the shaft diameter overall and the slot, although I think circlips may be too thick for the slot, eclips seems to be thinner spring-steel. Or get a used motor, but they are about ten times the price if you can't find a clip of the correct size.
paulh4

Well good news and bad got some e clips so have found one that fits into shaft problem is how to you put the out this back together. Now I have tried but after sorting out the spiral end and inserted the pin into it and making sure that the end sits flush so I can put the nut on the other end that goes into the gear wont line up and the videos online the guys are doing this on a bench not on the car if I get the other end onto the gear then the spiral part wont sit flush very frustrating been at it for about 40 minutes then it started to rain cats and dogs so I have had to abandon it till its dry again and suggestions for putting it all back together without a lot of hassle
PW Creswell

Now I know the gear has to go back to park and it uses a piece of plastic on the bottom of the gear to touch a little plastic button on the base of the gear box so I gather it always has to be in the park position so how the hell do you line up the hole cause as soon as I put the peg into the end of the spiral and seat that the hole isnt over the centre shaft on the gear
PW Creswell

Punctuation please!

The only bits of plastic I can think of involve the park switch, which is a cam that clips into one of two places on the back of the large gear (1st pic), and the 'button' on the park switch and connector block that should just push clip onto the gearbox casing (2nd pic). There was an earlier round GT motor with a different park and connector arrangement but you shouldn't have that. So you need to confirm which you have, and the type I show will find it's own parking position once its reassembled.






paulh4

Look at Mike's picture on the 6th, which I've reposted here. The large nut over the end of the tube screws onto the cylindrical fitting round the spiral rack, then that slots into grooves in the gearbox casing. The pin on the end of the con-rod is shown engaged with the fitting on the end of the spiral rack.

You will have to push and pull the spiral rack and its connector in or out until the spacing between connector on the end of the rack and the crank pin on the large gear are the right distance apart to get the connecting rod fitted to both.

With the blades off the glass that should move easily, if it doesn't that's why your wipers aren't working as they should.


paulh4

Yeah that is what I did do and now the thing isnt even turning on all back the way its should be and nothing from the motor yet it was ok before ahh well back to work tomorrow so no chance of looking at it till next week sometime
PW Creswell

In a lot of ways that's the easy one. Just check for 12v between the red/light-green and black wires in the harness plug while its pushed into the socket on the motor. If it's there then you've done something inside the motor. If not then you need to work back towards the switch.

This could run and run ...
paulh4

PaulC,
I'm very much into many repairs and servicing basically boiling down to clean and lubricate because this is my experience and not just with old cars.

Also with these old cars in particular you need patience - something that I have very little of when working on my own car but am fine with when working on others.

Sod's Law applies more often than not, often repairing one thing can bugger up another, or you discover more, hence my "shipwright's disease" approach of going from one end to the other to at least identify other potential work required. This is from over 30 years experience of running "classics" as dailies, doing the least to just get things going often comes back to having to repeat that work, sometimes more than once, to do the work properly to resolve the problems and issues.

I'm not talking about major stripdowns or spending huge chunks of 'fun' time fiddling with bits just getting the job done as much as possible the first time and not having to revisit it, or at least not too often.

As I put before, if possible, a second person at the car with you can sometimes see what you may miss because they're not so involved as yourself.

What to do now (IMO).
Have the wipers at least off the screen.
Take the motor out.
Have the rack extended further out at the motor end than usual - do not fully withdraw it or run it out of the passenger side wheelbox unless you know you can refit it without dismantling more than you want to.
Clean and inspect the areas of rack you can and see if there's damage.
If not damaged apply clean grease to those areas you can.
Do the same for the wheelboxes.
If you've not already done so, lubricate the wheelbox spindles with 3-in-One.
Try running the rack by hand to feel for catching, grinding, misalignment or whatever.

If you've not already done so, clean, inspect and lubricate the gear wheel and arm, inside and arm of motor housing.

Then you can start bench testing the motor.

Even with Rain-X (or equivalent) on the windows you can't really drive the car without wipers so I'm not suggesting a any lengthy period of sorting this.
Nigel Atkins

Nigel, how are you supposed to get at the wheelboxes to clean and grease them? Tucked up behind the dash they are invisible, let alone accessible. OK you can get to the LH one by removing the glove box, but the driver's side.....

I think it was one of those components where they put them in first, then built the car around them.
Mike Howlett

Very good point.

Apologies to all for that mistake.

Me rushing and editing as I went along.

The wheelboxes were in with 'the areas you can see' but got moved to give a more logical path of work and I forgot to add something like 'if you can see them' or 'I can't remember if you can easily get access to them'. Hence my preamble of "I'm not talking about major stripdowns or spending huge chunks of 'fun' time fiddling with bits".

I generally can't remember the details of me working on my Midget yesterday (I was actually working on it two days ago) let alone my BGT about 30 years ago so I have to resort to generalisations and try to remember to put in (can't think of the correct word now so) provisos.
Nigel Atkins

Being away at work your mind wanders and thinking about the motor it was working before just the nut had worked loose and that caused the spiral/rod to come out further at the motor and that it should do hence having to strip down the gear box in order to push the spiral rod back in place now I know inside the gear box there is a bit of plastic that allows the little arm to sit in a parked position but if this was moved slightly when putting things back together could this then cause the motor to not work because the gear isnt in the parked position like it should be .hope you guys know what I mean cause I will check if power getting to motor if yes then to me next logical step is to strip down gear box connect power and run it to make sure gear is in parked position before rebuilding it back together making sure not to move gear wheel
PW Creswell

What bit of plastic? Show us.

The only bit I'm aware of is as I said before which is the park cam which pushes into the back of the large gear. If that is missing it won't park i.e. it will run continuously. But you shouldn't have been anywhere near that to reconnect the tube to the motor.

There should be no need to strip down the gearbox to get the tube correctly fitted, just push the spiral rack back into the tube, connect the end of the tube to the end of the gearbox, and refit the connecting road, all as previously described.

Also as said before it doesn't matter where the large gear and the rack are positioned when you reconnect them, they can only go back together one way, and when the motor is powered and it runs it will park when it gets to the park position. It doesn't have to be reassembled in the park position.

However if you have moved the park cam on the large gear it could well park on the other side of the screen so you would then have to correct that. You might also have changed how the rack interfaces with the wheel boxes so don't run it with the blades on the glass until you have got them running and parking, to make sure they only sweep the glass.

paulh4

"However if you have moved the park cam on the large gear it could well park on the other side of the screen so you would then have to correct that. You might also have changed how the rack interfaces with the wheel boxes so don't run it with the blades on the glass until you have got them running and parking, to make sure they only sweep the glass."

Yeap that's all that I did wrong when I done mine.

Which is why I say to take notes, drawings and photos before, during and after. And why I suggest doing as I say not as I do because I didn't follow my own advice and got it all in a right state with the wipers going to the bonnet and not screen.

It's very easy to get too involved in trying to sort things to stop and make notes, drawings and photos and think about what to do logically, testing and so on, but often stopping and doing so makes the job a lot quicker and effective.
Nigel Atkins

No I haven't touched the plastic cam under the gear only took lid off gear box to make sure the spiral was seated properly and put it back together I only mentioned it because it was working before so seems odd unless it's the brushes on the motor but as I said at work 11 to 11 so wont be able to look till Monday checked out connection to motor possible a wire has been knocked out at the back or wiring issue further back
PW Creswell

The parking ramp (cam?) on mine fitted in very securely so I doubt it's moved on yours just by taking the motor housing lid off.

Touching anything on these old cars can disturb something else in the circuit or system or other items nearby, particularly if previously work and parts weren't the best.

Your motor could suddenly pack in but it's less likely and it was trying to do its job before. By the state of the wiring and connections I'd say it's more likely to be those but it might not be. You need to test the motor is wiring by direct electric supply or testing the wiring and connector to it. This also eliminates other wiring, connectors and switch.

You did have the ignition switch set to power the wipers? I often forget this when testing lights.


Nigel Atkins

Update put everything back checked and double checked that it was all sitting correctly and washers in proper place etc checked that power is going to wiper motor and nothing now unchecked fuses one was blown swapped it out while I was messing around had the cassette player on old tunes lol anyway it stopped working when I went to try wipers so now when I try wipers they blow the fuse make no noise so could they be jammed somewhere and that is causing on overload thus blowing fuse ?
PW Creswell

Update put everything back checked and double checked that it was all sitting correctly and washers in proper place etc checked that power is going to wiper motor and nothing now rechecked fuses one was blown swapped it out while I was messing around had the cassette player on old tunes lol anyway it stopped working when I went to try wipers so now when I try wipers they blow the fuse make no noise so could they be jammed somewhere and that is causing on overload thus blowing fuse ?
PW Creswell

Paul and others know all about electrics much, much more than I.

Did anything get hot, the motor, the wiring?
How quick did the fuse 'blow'?
What else is on that fuse?

Being untechnical this is how I describe it - fuses melt really, over time, very fast (almost) instant to (possibly relatively speaking) slow melt over time. From overload (overheating) and a fast melt (blow) is usually from a serious more instant overload like a short circuit (wrong connection, water or other spill/ingress, wrong contact(s) such as wire(s) touching) and a slower melt from build up of overheating.

The fuse is there to protect the circuit wires often sacrificing an item and/or or itself in the process.

As you've learn it's no good replacing a fuse until you discover or know the cause of the fuse going, worse would be the fuse doesn't go or quick enough and more serious damage is done to the wiring or other items.

Are the wiper motor and/or the wiper mechanism the cause of the blown fuse, if you were able to freely move the rack and wipers by hand when disconnected from the motor then I doubt it's them, this is where an independent (bench or circuit bypassed) test of the motor would come in.
Nigel Atkins

Wiper motor heater and radio are on the one fuse that's how I know fuse blew as I had the cassette playing while I was putting the bolts that hold the motor in place as soon as I went to turn wipers on radio went off and didnt hear any kind of noise coming from motor so figured it must be bad connections exposed wire all was ok before although wipers didnt go back and forth you could hear the motor now nothing so maybe in the process of sorting wipers out an earth wire has come loose?
PW Creswell

An earth wire coming loose won't blow a fuse, unless it touches a live wire perhaps.

Whilst a stalled wiper motor will take more current than a running one I wouldn't expect that to blow the fuse. Other things on that circuit could take the fuse over the top although I wouldn't expect a cassette player to be enough, and it would depend on what rating of fuse you had in there, should be a 35A.

How did you check power was going to the motor, unplugged?

You are going to have to disconnect the motor from the rack cable. Firstly to be sure that you can manually push and pull the rack back and fore to turn the wiper spindles (blades off the glass), and then to apply power to the motor (from the harness plug) to see if that runs the motor or not, and if it blows the fuse or not.

Until you do that you are just groping in the dark.
paulh4

Personally I'd take the radio/cassette and/or its live supply(s) out of the equation by disconnecting the power supply(s).

I put supply(s) as the radio might have a permanent live supply to power some processes on it as well as the switched live supply for turning the rest of it on it or off.

If the wipers and radio/cassette and its supply(s) wires share the same fuse then it might be the radio/cassette or its supply wire(s) or connections that might have caused the fuse to go rather than the wipers.

Given the state of the wiring shown so far I wouldn't assume that the radio/cassette is wired to the usual convention.

Also bearing that faults can be from a combination or permutation of issues or there could be seperate faults that you discover, or even cause, with your work in that area.

Its always best to cover the basics first before moving on, ignoring them to speed up the resolving of the problem often just slows the process down and often you can't successfully move on without having done the basics. Those notes on problem solving are from experience of previously going about it wrong (and still do sometimes even now).

Bench or bypass test the motor then you know if the motor is faulty.
Nigel Atkins

As the radio/cassette seemed to have been playing until the wipers were turned on it's unlikely to have been that as a _direct_ cause of the fuse blowing.
paulh4

Possibly not but the combination of the two might, unlikely suggests assumption and you know what assume makes . . .

Plus as I put, with the wiring on this car who knows!

And as I've put before if you're dealing with the wipers and the radio/cassette is off the same fuse checking it and its connections out clears it whilst you're in that area.

I agree it's more likely to be the motor but again that's an assumption.

I used to have to persuade a professional fully qualified electrician to do more tests and checks rather than just get something working again at that time only for it to fail again and mean perhaps a return journey of several hundred miles later to sort it again and to avoid a verbal ar*e-kicking from his boss and relentless mickeytaking and references to it until the next oversight was made.
Nigel Atkins

The combination is what I suggested as a possibility above, and it's why I said 'direct'.
paulh4

Sorry the use of the underscore/underline lines confused me, I've not seen it's use but once before. What do they mean/convey please?
Nigel Atkins

This thread was discussed between 24/09/2020 and 16/10/2020

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