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MG Midget and Sprite Technical - Starter motor lazy

Good evening all

Now I've just managed to refit the sump after 6 months of messing about. Don't ask.

A bit of a tale so please bear with me.

Fresh oil was put in, and turned her over without spark to get oil pressure. Very slow to turn over, even with the battery fully charged. So took the plugs out and she turned over fine, but the turning did slow down after a while. As the car had been sat for 6 months without being used I suspected a dud battery. However it was still within warranty to took it back and got a replacement, EVEN THOUGH the nice man at Halfords (and he is a nice man) checked my old battery and said it was ok.

So, I was very excited when I attached the new battery, expecting the car to turn over like a nun on a cheap bottle of house wine, but nope, did she chuff.

Took the starter off, checked brushes, all seems ok, cleaned the copper bit on the end of the motor, whats it called? Bendix moves fine. It spins fine on the floor, but didn't jolt as much as I expected. But, there was a strong spark when touching the red jump lead to the battery, if that means anything.

Anyway, I've checked all the connections, earth strap is fine, and anyway, with the starter in I've put jump leads directly onto the pos and the mounting bolt, and nothing. She doesn't even want to turn over now.

I also changed the starter solenoid, and just get the dreaded click.

So, unless the starter is somehow jammed, before I spend a ton on a high torque starter, is there a way to check the windings? Like I said, there is plenty meat on the brushes. When I get the starter off I can post pictures.

Even before I took the sump off, if she didn't fire fairly quickly, turning over would slow down quicker than I would think. And again, that was with a good fresh battery. Are these the signs of a starter on its way out?

Many thanks
Matt
Tarquin

Is it just a tired starter motor? I recently had the engine reconditioned and found my current starter motor, obtained from a scrapyard in Wales didn't have the power to turn an engine in good condition.

Got a new standard motor and this starts the car without a problem. No need for a high torque one
Gus

there was a thread like this recently (starter, solenoid click) but I can't remember the outcome or details but if you can find it (archives?) some suggestions will be there

you can test if the starter moves freely at least by turning the square on it

did the nice man do a drain charge on your battery?

as it happens the latest John Twist video covers batteries

all earths and all live connections will need to be clean, secure and protected for best results
Nigel Atkins

As mentioned, all connections are clean and new. Earth strao is new. Car has been to Le Mans and back since the rebuild, so it has been fine before.

How can I check the starter is 100% ok? Is there a way?
Tarquin

sorry I totally missed that you had a brand new battery I must have had screen scrolled up

you can test the starter turns in situ with a spanner on the square

but if there's a click I think your trouble might be before the starter

sorry you'll have to wait for someone other than me or look for that thread

I know the risks of sparks, H&S and all but could you disconnect the car from the battery but connect the starter to a battery with the starter in situ to test how quick it turns on the car(?)

Nigel Atkins

Earth strap is new, but is the contact with the body ok on all connections? A fresh paintjob insulates well enough...
Just a thought.
Alex G Matla

Hi Matt,

Click from the solenoid just confirms that is working OK, but the motor itself isn't. (I guess you know that much!)
The pinion may be jamming too tightly against the flywheel - Some of the starters use a spacing collar where they bolt up against the backplate, and if this is missing they penetrate too far and get jammed.
Or it could be the windings in the motor. If the field coil was shorting internally it could still spin, but the magnetic field would be weaker and you get less power out.

Can you borrow another just to try? That way you would know whether a standard exchanged recon one would do (cheap) or if you have to upgrade to an expensive high torque one.
And, .. are you sure that your new battery came fully charged?

Guy
Guy Weller

All earths have been rubbed back to bare metal.

Hi Guy, yes I am trying to borrow a starter. Andy hasn't got one tho, so thats why I'm trying to figure out how to check the windings.

I did put the new battery on charge, but to be sure I will use my fancy smart charger tonight to charge it again.

I can't understand why the starter has suddenly got even lazier after I took it off and checked the brushes! I thought it would improve things but it made them worse.

Another thing, the earth leads were getting warm as well when turning the engine over. I can't remember if this was with the old solenoid tho, which seems to be kaput. Shame as it was one of those with the manual over-ride, which the replacement one doesn't have.

Tarquin

you can also get click sounds when a battery is dead or off a bad/broken connection somewhere that can be difficult to pin down to the solonoid from sitting in the driver's seat or standing by the driver's door whilst turning the ignition key

which earth leads were getting warm (or all of them)?

the starter is well bolted in and making good and clean earthing contact to the engine?

where are the leccy boys at the moment, they'll return no doubt
Nigel Atkins

OK, think I've sorted it.

The little plastic insulator that goes around the pos terminal on the starter was cracked. So as I tightened it up it shorted out even more. Will try a place I know tomorrow that recons starters & alternators, otherwise it's Moss.

Matt
Tarquin

when you got the new battry, did you remember to sacrifice a virgin goat to the electric gods...that will do it


prop
Prop and the Blackhole Midget

well done

it does now remind me of another method of finding, switch the lights off and look for the sparks in the dark

a favour of Guy's for ignition problems and how many years ago I found a faulty HT lead I didn't know about
Nigel Atkins

Tarquin, I would favor the local place to redo the starter.
I find them more reliable then the "big guys" who go for just cheap.
Arie de Best

Eyup Arie
Yes I agree. The rest of the starter is fine, just that piddlng little plastic insulator! Quite pleased that I did actually find something wrong, and it didn't point to a problem with my loom.
Tarquin

Certain its not jammed?

I would stick it in gear and push it - and get someone to watch if the started motor is going round (you should be able to see the shaft of the starter motor sticking out the back of it - definitely can on a 1500)

C
C L Carter

Come to think of it, had exactly the same with a brand new starter. Albeit it stopped working completely. Was replaced under guarantee for the other type without the plastic insulator piece.
Alex G Matla

Starter motor refurbed for the grand sum of 20 quid! It was either that or pay a fiver for new bushes ... nowhere sells the little plastic insulator on its own. Shotblasted, painted, rebushed and new brushes. Bargain!
Tarquin

Sounds like a good result Matt!
Guy Weller

yeah but does it start the car !

:)
Nigel Atkins

Well some progress has been had.

Turns out that the replacement starter solenoid was also knackered, even though it shows continuity when energised. Bit odd that. So I found a new one in the spares box which works fine.

I still think the old starter was shorting out, causing another problem, but thats now sorted.

Oh I have also added a second earth direct from the battery to the bellhousing.

So the engine turns over. The battery is fully charged. But the rate of turning over slows down after about 10 seconds of turning over. All I can do now is jump the big battery from the Monjo to try and eliminate the battery.

I have also found another starter that I might get reconned as a spare.

Only other thing I can think of is that the compression ratio is quite high, about 11:1 I think. Would this result in the turning over slowing down? Guy, what were the symptoms when you had your engine reconned and you said your old started wasn't up to the job?

I have found a way to test the resistance of the windings on the starter, but it needs stripping down to get the armature (?) out. Thats the only other thing I can think of, is the windings are shorting internally and not letting enough current through.
Tarquin

Matt,
"engine reconditioned" - that was Gus, not me.

Touch wood, I have never had starter motor problem. But then the key to this is having a car that fires up instantly. Mine usually fires as it turns over the first compression stroke, and turning speed isn't really the issue.
Guy Weller

faulty new solenoid - I think I've seen that recently elsewhere

click but still the solenoid not working, yeap heard that before too

I could but wont put the usual full blurb on don't trust new parts or parts already fitted to be working correctly

there's a recent John Twist video that might help you (drain on battery)

recent recon engine(?), much higher compression than standard, old starter - as Prop would put what could possibly go wrong

the old starter shorting would that explain the earth leads getting warm because that didn't sound good to me

what spec is your battery?
Nigel Atkins

Battery is a Halfords 330 amp. Would think it would be fine, but we all know what thought did.

Can you post a link to the John Twist vid? The drain on the battery is interesting.

I'll drop the other starter off today for reconning, if that doesn't sort it then it must be the higher comp that it ia having trouble with, and i might ask permission to buy a high torque starter....
Tarquin

vid - http://www.youtube.com/watch?v=kgl7ikq_YOs&list=UU40j4KqUJPMVv4FQ29ro-xQ&index=2

200+ more here - http://www.youtube.com/user/Universitymotorsltd
Nigel Atkins

Jumped the monjo battery onto the Midget, cranks over fine with no slowing, so looks like the new 330 amp battery is just not up to turning this engine over properly.

But I just might try a high torque starter, I reckon it would be useful with this big fat weber.
Tarquin

it's a bit chicken and egg, you need to start the car now but once the engine has loosened up and/or you've fitted a bigger battery or hi-torque starter you might be ok with what you've got now (if you follow me, Guy never can)

if you've got or are going to add more electric items especially items like an electric cooling fan a bigger battery or hi-torque start that will take less out of any battery will be more required

just fitting a hi-torque starter may be enough to keep the present battery or at least until the warranty runs out

or fitting a bigger battery may mean that you can keep the existing starter

personally I'd go for a hi-torque starter or if you can get one to fit a small light starter off a Japanese car

I couldn't find the site I wanted so from two below will have to do -

from site one -
'Cold Cranking Amps
Cold Cranking Amps is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. The rating is the number of amps a new, fully charged battery can deliver at -18° Centigrade for 30 seconds, while maintaining a voltage of at least 7.2 volts, for a 12 volt battery. The higher the CCA rating, the greater the starting power of the battery.'

and two -
(more tech info) - http://www.motionbattery.co.uk/car-batteries-information.php

'so from these statements the best thing to do is get a battery with the highest AH and highest CCA. The only problem here is that battery's CCA and AH value, are proportional to the physical size of the battery; the bigger the battery the higher these values can be. Most cars have a specific location for the battery, and therefore you are restricted as to the maximum size of battery you can use.'
Nigel Atkins

Im not very knowledlable on electrics but on my 1500 I changed the battery from a 45Amp to 55Amp for more pull.
What is a 330Amp battery?
Arie de Best

330 will probably say 330 CCA. which is cold cranking amps which in basic terms is how much it chucks out when cranking for starting .I'm sure one of the electronics gurus can explain it better though.
Ed H

Good enough Ed.

Here's the blurb from a site called topbuzz.

Cranking power:
As the temperature drops, the cranking power required by the car increases. However, as more cranking power is used, the amount of battery power available decreases. Cold Cranking Amps (CCA) is critical for good cranking ability. It refers to the number of amps a battery can support for 30 seconds at 0°F until the battery voltage drops to unusable levels. For example, a 12 volt battery with 600 CCAs means the battery will provide 600 amps for 30 seconds at 0°F before the voltage falls to 7.20 volts (three cells). The higher the CCA, the more powerful the cranking ability.

If you live in a cold climate, you should consider the CCA rating when choosing a battery. If you live in a very hot climate, you don't need as much CCA.

An Amp (or Ampere's) is the stand unit that current is measured at. If there is a 1 volt drop across a 1 ohm resister, then 1 Amp is drawn. This formula is know as 'Ohms Law'. However an Amp is a BIG unit, for smaller electronic devices (i.e. computers) its usually measured as milliamps (mA) which is 100 th of an Amp

Lawrence Slater

(mA) which is 100 th of an Amp --> divided by ten that is
Alex G Matla

Well spotted Alex. I didn't proof read that, I just lifted it.

mA is 1000th of an amp.

Looks like the extra 0 got lost betwen the previous 0 and the th.
Lawrence Slater

are my posts invisible?

Arie,
45 to 55 amps isn't more pull as such it's more capacity

http://www.youtube.com/watch?v=kgl7ikq_YOs&list=UU40j4KqUJPMVv4FQ29ro-xQ&index=2

and 330 CCA can be measured to different standards so one set of 330 CCA isn't the same as another (that's why some sites quote two figures for CCA for two different standards - http://www.motionbattery.co.uk/car-batteries-information.php
Nigel Atkins

Yes nigel, completely. Did you post something?
Lawrence Slater

yes, my battery only has 330 CCA. The Varta and Bosch's that I'm looking at have 5-600 for a similar physical size - massive difference! I've taken the new Halfords battery to work and put it on a forktruck, it will be fine for that. And I'm having a new Calcium battery or similar, and a high torque starter. I want to use the car regularly, and I think the SW10 cam can make it difficult to start sometimes. And anyway, the wife will be driving it as well, don't want a phone call that the damn thing won't start.
Tarquin

as an example with this link you can see the 063 battery from Bosch (S5 HSB063) label shows 520A to EN standard and 52 Ah

also note the 6 amps bench charging

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_734795_langId_-1_categoryId_165762#tab2

EN standard -
'EN: This measures the current available when draining the battery for 10 seconds to 1.25 Volts per cell'
http://www.motionbattery.co.uk/car-batteries-information.php

Nigel Atkins

I bought a Jap battery at the weekend. About 400 CCA I think, which was one of the best for the physical size.

Using the old starter motor, the car took, in total, about 2 mins cranking to get started. The new battery was much better than the Halfords one. It only started slowing down at the 2 min mark, and not by much. The Halfords one used to start slowing after 15 seconds!

I know that the car being sat unstarted for 6 months might have contributed to the slow starting, I'll see how it starts tonight after being sat for a couple of days. You can get Isuzu Trooper starters on ebay for 30-40 quid.
Tarquin

"You can get Isuzu Trooper starters on ebay for 30-40 quid."

Will the Isuzu starter just bolt in, or does it require an adapter plate?

(Sorry about the thread hijack)
BH Harvey

"I know that the car being sat unstarted for 6 months "


6 months?
You should be ashamed!
Wouldnt it be better if you would buy a mgb or so? ;)
Arie de Best

Mmmm I'd like a BGT. But it would end up sat being unloved while i finish off this V6 midget I keep on about ... :-O
Tarquin

if you were cranking for 2 minutes even in burst it's no wonder things got hot

perhaps you needed to turn the engine by hand with plugs out, then leave the plugs out turning the starter just to loosen the engine a bit and move the oil a bit before putting plugs back in and trying for real (I think I got that right)

2 minutes, carry on at that rate you'll burn the starter out :)
Nigel Atkins

6 month old petrol and then not atomised. Cylinders probably flooded with liquid petrol from when using the slow, faulty starter.
Will be better at the next start, and better still when you have some fresh petrol in it.

You could always get Lizzie to push start it for you.
Guy Weller

at least BH wont have that problem with his starter as his petrol's not making it to the pump

11:1 would want some nice fresh 99 octane too

is 6 months long enough for the petrol to go off?
Nigel Atkins

Went straight to the petrol station and put some 97 in, could do with finding somewhere that does 99. £40 to fill the tank, it was shocking!
Tarquin

Did anyone check the float chambers had new fuel in at any point?

..... I'l get my coat.
Dave Squire (1500)

Tesco for 99 I know you have them up there my wife tells me
Nigel Atkins

This thread was discussed between 20/03/2013 and 03/04/2013

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