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MG MGB Technical - Ignition Switch and Lock

I am in uncharted territory with this - Have not long purchased this sadly neglected 1973 GT,over the net, and it came from the other side of the Australian continent. Previous owners,(non enthusiasts, spent lots of money for garbage add-ons like an immobilizer etc. Because I am will be restoring it, I have removed the immobiliser, however, due to the cretinous butcher who fitted it, I have to almost rewire the ignition harness.

I have the Lucas/Bentley/Autowire wiring schematics for the 1973 model year, and am attempting to align the damaged wiring to normal. I noted the positions of the wires when I pulled them off the rear of the ignition switch.

I am now getting a short with the Brown ignition wire when trying to connect it to the rear of the ignition switch (same position as before) Can someone put me out of my misery, by advising which wires attach to which spade terminal? I have (A) 1 x Brown ignition wire (B) 1 x White/red (C) 1 x White/green (D) 2 x Whites. Also, the screws holding the ignition lock/switch together, are recessed and I cannot get at them to remove the lock/switch? Thanks, Maurie


R M Prior

Maurie.Since no one has posted yet, allow me to attempt to help. My 79 may have a different ignition switch than yours, but, from your photo, they seem to be similar. On my car, the plastic electrical switch seems to be held in place with a single cross point screw that comes in from the bottom of the metal "ring" portion. Removing that screw allows the plastic switch to be removed from the assembly. I used to have an assembly without the plastic switch, but cannot locate it right now, so do not remember how to remove the tumbler section of the assembly (the portion that the key goes into), but it is connected by a flat rod to the plastic switch portion.

As to the wiring hook up, the connections can be determined by using an ohm meter with one probe attached to the brown wire terminal. When the key is advanced to the r "run" position, it should be providing power through the white wire system. One of your terminals should show zero resistance on your VOM when the key is in this position. The other terminal (terminals?) can be determined in similar fashion. When the key is turned to start, there should be zero resistance between the brown wire terminal and the terminal going to the starter relay.

Do not have a copy of the 73 wiring diagram available, but they are available on the internet in printable form. Hope this helps.

Les
Les Bengtson

1973 differed quite a bit depending on whether it was North American i.e. the bulk of LHD or not, I'll assume not in your case, but there is a 'but'.

RHD switches should only have four electrical connections although there may be more spades, some of them being the same connection.

If putting just the brown on a switch encounters a short-circuit then the switch is faulty, earthing to the lock somehow.

But if other wires are on the switch the short could be on one of those and nothing to do with the switch. However the 'but' referred to is that North American switches/locks have extra connections one of which is earthed when the key is in the lock, maybe only when the switch is in the 'off' position, a brown on hear would be shorted to earth. See the two types here http://www.mgb-stuff.org.uk/isw.htm#73

It seems that replacement switches for RHD are now the same as for the LHD i.e. with the extra terminals, but these are left unused.

For the RHD type you can work out which terminal is which as follows:

In the off position all of the wires are isolated from each other.
In the Accessories position the brown and
white/green are linked.
In the Run position the brown, white/green and white are linked.
In the Start position the brown, white and white/red are linked and the white/green is isolated.
paulh4

From the other thread Maurie put -
"it is a GT, and VIN # is, GHD5-3266{**}-G, and is an English import into Australia I understand".

So assuming UK RHD, using Paul's illustration and one from web, image below.

The switch that Moss (UK) shows as 37H7708 has four sets of terminals, as below.






Nigel Atkins

Hmm
Having ignition switch written there where it is in that pic.'could be' misleading making you think the adjacent post is ignition when in fact it is power supply in
The connections are as follows---
Switches are usually numbered on the rear-

2- Brown- Power in (live)
3- White- Ignition and things that need power with ignition ON
5 - White/green- Accessories
1 - White/red- Start
William Revit


Thank you all for your great help, however, I am now even more confused, as the wire positions that were on this car are located quite differently from Nigel's 1st image. Remember, I have just bought this car, and the PO had an im-mobiliser fitted to it, but I removed it, and in that process I have needed to rectify the butchery wreaked upon the harness,by the cretinous auto electrician.

After removing the im-mobiliser, I replaced the ignition wires as I found them and have attached an image of the type of the current ignition switch (image 1) and the wiring positions as was and still are (my sketch image 2) I found that I could start and run the car, but maybe it is pure luck? Anyway, please advise me as to where to now?

The sketch is assumed to be looking from the rear towards the rear of the ignition switch, and I haven't numbered them as I cannot see the numbers, but the Brown is at 10'Oclock - the White/red is at 2'Oclock, the White/green is at 4'Oclock, and the group of plain White wires are at 8'Oclock.

Thanks, and always grateful,

Maurie Prior





R M Prior

Nigel's first image is a drawing, so the terminals are ordered for convenience in the drawing as a whole, they are not necessarily in the same positions as on the physical switch.

For example it looks like terminal 1 is bottom right on the photo, and it could be 2 or 3 bottom left. The others are not visible.

The terminal numbers on the drawing _should_ line up with the numbers on the switch as to what colour goes where though, as they have been taken from the original Leyland drawings. But to be sure and especially if your switch does not have numbers do the continuity tests I described earlier, and that will be conclusive - if the switch is good.

But it doesn't matter which way round you connect the wires, you still shouldn't get a short with the brown wire unless the switch is faulty or one of the other wires is shorted to earth. So in this case also do a continuity test from each terminal to the lock body in case the switch _is_ faulty.
paulh4

Maurie - given that mine is also a 73 BGT, I wonder whether you have the same lock/ignition unit as me - it has an inscription on the dark plastic rear : SWE and Germany; it has 6 terminals, and the numbers that appear to align with terminal spades are 57a (one spade), 15 (one spade), 50 (one spade), 75 (one spade) and 30 (in between 2 spades). One attached pic faintly shows the back view.
Cleverly, I don't appear to have marked the wires when I removed them, but the wires are: Triple white, single brown, single white/green and single white/red.
To put them back on, I will do the abovementioned continuity tests. Following Paul and others' advice, I'm sure you'll identify any short within your switch assembly - it sounds as though there is one somewhere.
John.





J P Hall

Those terminal designations are DIN numbers which post-date the original switches, but are seen on the cylindrical relays on late model MGBs as well as modern Bosch type relays. Listed here https://en.wikipedia.org/wiki/DIN_72552 but there are some multiple definitions.

It gives 57a as parking lights which is obviously not correct on an ignition switch.

15 appears in several places for different things one of which could be the ignition supply from the switch.

50 seems to be associated with the starter i.e. white/red which would be fair enough.

75 is radio and cigarette lighter i.e accessories.

30 was sometimes used for 'battery' i.e. brown and sometime starter, even the cylindrical relays labelled the battery terminal as 30/51.

Dual spades (Nigel's photo) are often for white wires as some years (including 1973) had three whites at the switch and I've never seen more than two wires in one spade connector, i.e. three whites would need two spades.

paulh4

Maurie,
I think you have the order right.

Normally I'd just go out and look at my 1973 Midget for you but it isn't with me at the moment.

When I forgot what order the wires went on to the ignition switch at Xmas 2008 I was given this advice that worked for me. -
"Get yourself a multimeter on continuity and first off find the permanent live post (on the switch not the wiring) then work round the other terminals noting which does what on the turn of the key. Then find the permanent live wire and install it and work out the purposes of the others"

Also follow the info given here in previous posts -

"For the RHD type you can work out which terminal is which as follows:
In the off position all of the wires are isolated from each other.
In the Accessories position the brown and white/green are linked.
In the Run position the brown, white/green and white are linked.
In the Start position the brown, white and white/red are linked and the white/green is isolated."

"2- Brown- Power in (live)
3- White- Ignition and things that need power with ignition ON
5 - White/green- Accessories
1 - White/red- Start"

Also see page 30 (of 34) here -
http://www.advanceautowire.com/mgb.pdf


Nigel Atkins

Just for Willy as he keeps me on my toes, "I'm shakin' the bush, Boss."


Nigel Atkins

Mauri
You mentioned--

"After removing the im-mobiliser, I replaced the ignition wires as I found them and have attached an image of the type of the current ignition switch (image 1) and the wiring positions as was and still are (my sketch image 2) I found that I could start and run the car, but maybe it is pure luck? Anyway, please advise me as to where to now? "

Does this mean that you have currently got it working as it should do without faults -?
If it starts and runs I'd think your work is done-

willy
William Revit

As long as it also switches off with the key :o)
paulh4

Din numbers - thanks for the heads-up Paul. And Maurie for the timely thread!
John.
J P Hall

shakin the bush,-- Nigel

Always a pleasure to chat with you mate, shame there's nothing about switch wiring in 'the' handbook----lol
William Revit

Maurie
If it starts and runs and turns off ok but is hard to start, you 'might' have ignition(white) and accessories(white/green) mixed up
Going by all the posted diaghrams on here it 'could' be a possability

Easy to check---turn the key to accessories,--
'If the ignition light comes on in the accessory position the white - white/green need swapping over on the switch
"if the ignition light doesn't come on in accessories but does come on in the ign. on position you've got it correct

willy
William Revit

On my 73 the key movement between accessories and ignition is much smaller than from off to accessories or ignition to start, very easy to go straight from off to ignition - and hence get the ignition warning light, unless you try. That's with two locks albeit only one switch

But if you have the white and the white/green reversed it won't start while you are holding the key at crank, as that terminal is disconnected there as described earlier. If it only ever fires as you release the key, then they may be reversed.
paulh4

I can't recall now but is it that there might also be a problem with the starter solenoid or starter if it cranks over at holding key at crank position but doesn't fire until you release from that position, or is that from another cause?
Nigel Atkins


Thanks all,

William Revit said -"Does this mean that you have currently got it working as it should do without faults -?
If it starts and runs I'd think your work is done-?

Yes, and No. Yes, because, from the off position all is good, then, the key now turns to the first position, the ignition light and the fuel pump come on in the second position, and the car starts in the third position, so all good, however, I am not comfortable with the brown wire, where it attaches. I get a spark when I attempt to slip it on the appropriate terminal, however....and I am bewildered over this....in desperation, I made up a short intermediate wire, (male one end and female t'other) connected it back together, and no sparks! Figure that one out! Not being a dab hand with a Multi-Meter, I am unable to do these tests, however, I have ordered a new meter and can get tuition in how to understand it.

Maurie


R M Prior

Could perhaps be -
. a poor brown wire connection to its (female) spade terminal
. poor brown wire spade (female) connection with the switch (male) spade
. something wrong with the switch itself.
Nigel Atkins

Didn't mean to press the 'Submit' button then, that was only half a post and I was called away.

I'll try again.

Subject to correct wiring of switch, could perhaps be -
. a poor brown wire connection to its (female) spade terminal
. poor brown wire spade (female) connection with the switch (male) spade
. something wrong with the switch itself
. combination or permutation of any of the above.

The brown wire shouldn't spark off the switch if the switch is in the Off position, perhaps there's wear or a fault in (electric part of) the switch then, testing may require the inclusion of wriggling wires and connections.

Best usually not to connect or disconnect a live connection without the battery being disconnected.

Where you put in your post "the key now turns to the first position" if it didn't before does this suggest the key barrel part of the switch is worn/faulty? From your photo I can't see any clear markings which may suggest the part is very old/worn.

('Submit')

(and 'Edit this posting' and 'Submit' again)

(and 'Edit this posting' and 'Submit' again)

Nigel Atkins

If the key is turned to the off position you should not get a spark when tapping the brown wire on its terminal. If it does then it will be discharging the battery while parked, unless you have a full battery disconnection switch, and by 'full' I mean one without a bypass fuse.

If you suspect that it is sparking take all the other wires off and see if it still does it.

"I made up a short intermediate wire, (male one end and female t'other) connected it back together, and no sparks!" If the engine still started and stopped as it should, then I suspect the 'spark' you are seeing is not in fact occurring, but some trick of light reflection. Anything else would be 'magic', but not for nothing is electricity known as 'electrickery'.

Nigel's question of 14:51 yesterday:

There can be two different faults - the one where it only fires when you stop cranking can be caused by weak sparking, not normally with rubber bumper cars with a working coil boost circuit, unless the 6v coil has been changed for a 12v.

The other starting problem that usually only affects cars with a working coil boost system is where it fires when cranking but cuts out when the key is released, and that is caused by the ballasted connection to the coil being faulty. Faulty ignition switches can cause it on both boosted and non-boosted systems.
paulh4

Chers Paul.

I wa actually thinking of a straight forward system, like on my Midget, with 12v, no relay(s) or ballast, something in the back of my mind about the solenoid or starter perhaps - or I might have misremembered.

I don't think the mild damp winters we now get helps, so much condensation that really sneaks its way into metal, electrics and electronics.

O/T
I've just spent 45 minutes going in and out of the misty rain/drizzle as a low battery warning on a non-car item was flashing. Changed to new batteries but no change to flashing, done a bit of poking around, cleaning and spray of GT85 as I've run out of other stuff, put the original batteries back in, all is fine (so far).

I've recharged/reconditioned/trickle-charged 4 car batteries for 3 of my neighbours, 2 of the batteries too low to start the cars other 2 very low.

Checked my Midget, it was fine, so check my wife's modern car and that's low. Cold then wet weather and cars mostly just sitting not getting driven or not far - car battery must be through the roof, many unnecessary sales too.
Nigel Atkins

That's more likely to be the first one. I was on an organised run a while back (well, it would have to be ...) and a C wouldn't start even though it seemed to be cranking well enough, but with a push-start it fired up straight away.

I reckon a lot of people replace batteries when all they need is a boost charge and that will restore capacity, once flattened the on-board charging system only puts about 50% of the capacity back.

The ZS needed one about once a year as it was used so little in the summer, even though everything bar the radio and clock was on a cut-off switch. When I sold it the battery was 13 years old The only time the V8 has needed it was after a year's lay-up for a problematic engine rebuild and repaint, again for three month gearbox and OD rebuild, and it needed the booster pack a couple of weeks ago for the first usage in a couple of months as it started but I pushed the choke in too quick, it stalled, and didn't have enough oomph left. That's 15 years old.

Lithium booster packs are brilliant - always ready, and you don't need a donor as you do for jump leads or capacitor pack.
paulh4

As you know I'm a big believer in having a good quality battery in good condition and state of charge especially for classics where there might be starting or electrical issues.

I also repeat what JT says about car batteries being one of the most oversold car parts (as I told my mate when the RAC man tried to sell him a new battery at the roadside, that I later revived for him after he'd bought a new battery from elsewhere, even my mates won't listen to me).

I think the problem is speed/time, modern drivers want or need a very fast recharge of the battery and the equipment to do so. This often presents further issues even if it resolves the initial issue.

Often the battery discharge is low over a long period of time so the recharge needs to be low and over a good period of time.

I use either or a combination of an old "4 amp" charger, that's not really ever going as high as 4 amps, and an old Carcoon (Accumate) inflator and "four stage" "battery maintainer", it gives out constant 1.2 amps whilst doing main charging so it will charge a very discharged battery (down to 3v) but takes a couple of days or a bit more to do so.

These give a better and longer lasting recharge than many of the modern faster chargers, and some modern chargers won't even try on a battery discharged to 6v, or even higher.

I've been trying out a neighbour's Ring SmartCharge RSC612/RESC612 (why it has two model numbers I've no idea) "7 stage charger", it has many useful features especially for use on modern cars and a "Recondition Mode" which I have my own version of with using my combination of old chargers. Lowest setting I can see is 2amps (up to 12amps maximum and 0.8amps in "Maintenance Mode").

I'm not convinced in straight forward charging, even of very discharged, that it's as good as my old chargers and it never fully shows when the battery is fully charged in "Recondition Mode" at least as it goes into a sort of float showing 90% charged and then briefly 100% and back to showing 90%. Still the additional features do make it a very useful tool but I'd prefer a better thought out display and possibly better quality and accuracy make/model but it might be very good but I have nothing similar to compare it with.

https://www.ringautomotive.com/en/product/RSC612

Nigel Atkins

Couple of vids (vids and instructions are quite brief), no doubt most ordinary users with just press the Auto Charge button, that just gives the fastest charge rate the connected battery can safely take, rather than perhaps more appropriate lower and slower settings.

How to Charge a Car Battery with a Ring RSC612 Smart Charger - https://youtu.be/e4T5BSiUieY

How to Test a Car Battery with a Ring RSC612 Smart Charger - https://youtu.be/8vI1JoVkSl0
Nigel Atkins

Paul - back to your post on 25/1 - I can confirm that with the German 6-post ignition switch on my 73 BGT, the continuity test shows the following:

Brown to terminal 30* (See below).
White/Green to terminal 75.
White(s) to terminal 15.
White/Red to terminal 50.

* I have 2 terminals next to the 30 designation; both operate the same, but the one with the blue test wire shows slightly better continuity, so I will use that one.

A conundrum: there is what appears to be a spare unnumbered terminal at 12.00 in the attached photo, which shows continuity ONLY when the key is in the "0" position. On repeated testing, the terminal has no power as soon as the key is turned to 1,2 or 3.
Any ideas? - given that these switches apparently also popped up in Landrovers etc., I'm thinking maybe power to something fancy like a retracting aerial, alarm, or something useful when other power is off?
We never stop learning.
Yours,
John.


J P Hall

... or maybe a "don't forget to take the key out" warning/buzzer in some countries? - since that seems to be how it works. I shan't be connecting that one up to anything!
J P Hall

John,
I was just going to suggest that possibility of key left in, too late.

That blue test wire, the spade connector looks to have a lot space and wire drop off it's collar, it's probably fine, but is it crimped fully. See me after work and before you go home, and have your kit available for inspection. 😉

😁


BTW, well done on reporting back and adding to the pool of knowledge.

Nigel Atkins

Good spot Sir - just makin' sure you're awake Sir. Lucky it's just a test wire.
And yes, I benefit hugely from the pool of knowledge, so I feel it's a duty to add any snippet that helps.
Be interesting to see if anyone else has another idea for the spare terminal.
John.
J P Hall

Sounds more like a connection for the anti-runon valve, although that should be live whenever the ignition is off i.e. when the switch is in the accessories position.

On the MGB the 'key in' reminder outputs an earth not 12v, and from a contact on the lock body not the switch. Replacement locks for RHD cars can have both terminals wired to the multi-way connector, but there is no corresponding wire in the harness of course.
paulh4

John,
a possibly intermittent test wire will cause all sorts of headaches when testing and problem solving - be in very early tomorrow morning and we'll go through absolutely everything before you start work, best bring a breakfast you can eat on the go.

Paul,
could it be a redundant position to this (make/model) vehicle application, either generally or to some markets?
Nigel Atkins

As with the anti-runon and 'key-in' connections on RHD cars.
paulh4

Potential for possible mix and mismatch of replacement parts then, John had better get that test wire certified then. 😉
Nigel Atkins

Glad that's agreed then!
Today (our time) I'll be reconnecting the battery after 4 weeks' hard graft, so will confirm for the archives the correct connections on the German 6-terminal switch.
This digression hasn't helped Maurie the OP, but didn't justify a separate thread.
John.
J P Hall

John, Paul, Nigel,

Every comment whether exactly on thread or otherwise, is like gold to me where it concerns this general discussion. Every image, and every remark off the cuff and serious, are valuable sources of information to the likes of me, when I am travelling blind with this topic.

Thanks for EVERY comment - they are all appreciated!

Maurie P
R M Prior

I'm pretty sure you're hiding your light under a bushel, Maurie - but spot on with what you say. I learn so much (and try to put into practise) from info provided willingly and freely by the likes of Paul, Willy in Tassie, David Russell-Wilks (inspiring me to a better standard of work), and heaps of others. I thank goodness that so many of these clever and experienced people are willing to share and often expand upon ... and expect at most a Thanks Mate in return. That's why I love to put a little bit back, on the odd occasion.
I now have time (in retirement) to attend to TD, YA and ultimately my poor old TC - all the while sheepishly absorbing advice from higher mortals, like a sponge.
Enjoy the journey on your 73 BGT, and keep us all informed.
PS - did you do the continuity tests at the back of the ignition switch? - there was enough confirmation of yhe 4-post switch numbers, to probably just plug & play.
John.
J P Hall

Incidentally John - is that an LHD tin-dash in your picture?

I've realised the switch and possibly the lock is quite different to my RHD 73. My lock is circular and fits into a hole in the back of the lock, with a grub-screw through the side holding it in (B in the attached) whereas yours has 'ears' with screws that may be attaching it to the lock.

paulh4

Ha! - confused you Paul; it's a normal uk rhd, but I took the photo with the reverse phone-camera. That's why I couldn't get my ear out of the way. Scroll back up to my pic of the 25/1 and you'll see the front and rear views right way up. I'm assuming a po put an aftermarket German lock on at some stage.
John.
J P Hall

John

The lock is the same as my '78 Midget.

Dave O'Neill 2

Maurie,
I'm glad you put your post as I was going to suggest to John that perhaps knowledge of alternatives would be useful in itself and in case the 'DIN' switches were the only or best alternative given that whilst parts availability is very comprehensive and regular they do sometimes come and go and certainly the quality of modern made ones can sometimes be low.

The differences in parts used over the years and different markets of B (and Spridgets) production is very wide and still brings many surprise to me all the time.
Nigel Atkins

You did indeed, John :o)

Clausager mentions five different manufacturers so if the bodies and switches differ between them that makes replacement a bit of a lottery if buying sight-unseen. I have replaced mine (lock minus switch) but the new was the same as the old, just as well as at the time complete units could have been three times the price of the bare lock. Having said that the Parts Catalogue has a drawing of one 'eared' switch (the rest being circular but with differences) and that and Clausager shows it being used from Jan 72 to the end of CB, but my Sept 72-built 73 model didn't have that. Caveat Emptor.

Amusingly early Neiman locks were labelled 'Fahrt' and 'Start'.
paulh4

John,
good luck with the start up, wear rubber boots and have a couple of helpers and fire-extinguisher nearby just in case.

Perhaps I should be more careful as you look like a notorious guest of Her Majesty over here (or Tom Hardy if you prefer).

I expect you're out now riding around enjoying the fruits of your labour in the warm sun (it's sunny here but not warm and we're in lockdown).
Nigel Atkins

Dave,
good job I looked here as I was going to post on another thread if you'd seen the results John got from his switch here.

Yours has some unattractive bends to the terminals, probably part of the PO alarm installation or other work they did.

You might not have seen, I asked what DPO meant, I might have known previously but I've forgot.


Nigel Atkins

Nigel

DPO is basically the same as PO, just a bit more descriptive.

This, from the mgexp site:-

"What's a DPO???

If you own an MG or for that matter any one of the various LBC marques, then there is a very good chance that you have one or more of these "DPOs". Is it a part or a collection of parts on your car that you haven't been able to identify and maybe always wondered what it was and what it does? Is it one of those funny little terms that the Brits use from time to time to make you listen a little closer?

Okay, okay... I'm finally ready to let you off the hook. It stands for "Dumb Previous Owner". As I said, it's something that most of us have and we probably think of him or her from time to time when we are having to correct something they did to our car in its previous life."



The bends might have been induced when the radio wires were (oh so carefully) scotchlocked onto the ignition wiring.
Dave O'Neill 2

Cheeers Dave, I kept thinking of devious or deceptive and then thought perhaps it's nothing to do with previous owners. Perhaps it was my coping mechanism of protecting myself from being one. This also explains why Countdown is beyond me.
Nigel Atkins

Paul - also, the angle of the lock is all wrong because I had loosened the outer column and dropped the lock downwards for better access to the terminals.

Dave - so the terminal at 1.00 in your photo should go live when you return the key from 2 or 1 to "0". But once you take the key out and put it back in again (if you have time in your day), that terminal is again inactive until you come down from1 or 2.

Paul - at my age, Fahrt and Start about sums it up.

Nigel - yes, I'm far from photogenic. Handy in my first career where my clients were all on the wrong side of insurance claims. BUT, after a setback yesterday (tooth extraction), today will be fire-up day after checking all my front-end torques. I'm expecting 27 degrees (centigrade, not those funny other things), mainly dry but with a chance of a cloud.

My other favourite acronym is BFH. I won't go there.

John.
J P Hall

Good luck tomorrow then John, 27c I could put up with (need) now I'm much older, previously it'd be a bit too warm for me.

I should have put for your part of the world not Tom Hardy but Eric Bana.

I hope the tooth extraction was by your consent.

BFH is used for basic training I think for many mechanics here.

Nigel Atkins

I've just checked the connections on the switch. Results as in pic.

John, I didn't see your question about terminal 57a until just now, so didn't check whether it goes off when the key is removed.

Dave O'Neill 2

Thanks for confirming the connections on the 6-bunger ignition switch Dave - this will be useful in the archives, or Paul might even put it in his excellent reference site.
Had a setback today, not I think related to my recent reinstallations - the car cranks willingly but won't fire ... nary a cough or a fart. Tomorrow I'll check spark from coil and dizzy (Lumenition electronic setup), and we'll go from there. Very frustrating after 4 weeks' work on front suspension, steering, all buttoned up ... and the car won't start!
John.
J P Hall

Both picture and drawing duly added and attributed. I took the liberty of adding 'ears' to the drawing to match up with the picture ... and flipping the picture!
paulh4

Goodonya Paul.
My "failure to fire" appears to be fuel supply, so more testing tomorrow. Not to digress any more, Maurie!
John.
J P Hall

I have managed to get myself in a tangle with my posts, about two separate issues, the steering column and the ignition switch/lock. My apologies for confusing the two. Here is an image of the steering column after removal and the expected result from the collapse.

This is one of many reasons I love this car - apart from the butchery perpetrated by the DPO and an ignorant auto electrician on the steering column and the harness, the car generally has been unmolested. It has the original rubber flooring, carpets, and trim, (all need replacing BTW) but in general, it is a barn find of sorts.

I have to confess to a degree of masochism with MG's - I find a neglected example and I just have to restore it.

Anyway - I understand that new top and bottom bushes are available, are the nylon "collapsible" bits available or do we make do with something else? Thanks,

Maurie P


R M Prior

Maurie -
(1) It is very easy to fix the broken "semi collapse" feature using epoxy resin; I did mine a few weeks ago, basically following the Gerry Masterman (sp?) guidelines. One point: there may be a little rollpin about half-way between the epoxy shearpins, possibly only on one radius of the outer portion of the concertina section. There was on mine, and I've seen them in photos of others' - so I suspect inserted at manufacture. If not, I'd recommend you drill and insert a rollpin, as it helps hold everything in place during reassembly, as well as providing backup to the epoxy shearpins. Others might have a view.
(2) Do not forget to put your new lower bush over the (lower) inner column BEFORE you carry out the epoxy resin repair. Don't ask me how I know this.
John.
J P Hall

I used pop-rivet pins Araldited in. Bear in mind any repair hear will probably change the 'collapse' characteristics.

It's a bit of a struggle fitting the lower bush to a shaft column, but it can be done, forcing the bush over the lock slot from the wheel end.

Info on shear pins and bushes on both intermediate and later columns here http://www.mgb-stuff.org.uk/scolumn2.htm
paulh4

This thread was discussed between 23/01/2021 and 21/02/2021

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