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MG Midget and Sprite Technical - 1275 starter motor problem

I have just installed a new starter motor on my midget ( 1971). The problem I am now having ( and have always had) is that when I turn the key the starter motor will engage for perhaps 1/4 of a second and then dissengage not allowing me to start the car. When the motor dissengages I get a " hmmm" sound until I turn back the key and then try again to most times get the same thing over again . On odd occasions the motor will turn the engine long enough to start the car but only rarely. The battery is fully charged so this is not my problem ; could this be a grounding issue or does anyone have any other suggestions? Thanks.
lm Mayor

Likely to be missing teeth on the flywheel starter ring I'd have thought...
James Bilsland

I am wondering James if IM is actually trying to describe the starter being thrown out each time with a poor starting engine?

Have you been using this car on a regular basis before this starter motor problem began mate?
Robert (Bob) Midget Turbo

I had this problem recently. Turned out to be a dodgy solenoid that would not stay "on" when I held the key over to the start position. It would give the customary click... but then fall out of engagement. A new solenoid did the trick and starting has been as good as gold ever since
David Cox

Too late for IM but the new uprated starters don't need the solonoid but it can stay in situ or be rewired out of existence
Nigel Atkins

A starter that does not need a solonoid rather than a starter that has one attached to the starter body!!!!

eddie
Eddie Cairns

Eddie I am sure that is what Nige meant to say . :)
Bob Turbo Midget England

Thanks for the ideas guy , I will check for the solonoid when I get home and try replacing it as a first effort and it would be great if this would solve my starting problems. Is the solonoid to be found on the firewall or is it tucked away in a hard to get at spot? I never even considered this because I always thought it was built into the starter ( duh !)To think I have had this problem of only being able to get the engine to turn over intermittently ( or not a all) for quite a while now and it may be something this simple to replace to solve my problem. I will post whether this works or not . Thanks,
Leonard.
lm Mayor

Leonard

Your description of the fault has now changed?

Now you are saying that the starter sometimes does not work and other times it is fine.

Originally you stated that the starter engaged momentarily and then simply began to hum? or so I understood?

Can you confirm please what it actually does and when did the failure begin?

If the starter always engages and then disengages then it is probably not the solenoid.
Bob Turbo Midget England

Bob, you are right - the reported "symptoms" do seem to have changed!

Im,

It sounds to me that the Bendix is sometimes engaging, when it will start. And sometimes failing to engage, when the motor will spin with no load, producing a humming noise.

Likely therefore that either the Bendix needs a good clean (leave to dry, don't try adding any lubricant)

Or that the earth strap to the engine is in poor condition so that the motor doesn't always spin fast enough to engage the Bendix.

Guy
Guy Oneandahalf Sprites

Thanks Bob, Eddie (I think that's what I meant)

Good point about earth strap

A few of us are trying to convince a B owner to first check and clean his battery and earth leads and connections as he has starting problems as these are so often overloooked (and on a B beneath the car getting all the wet and grime)

When they first came out my mate had a V8 Disco about 18 months old wouldn't start all seemed OK we even checked the battery leads for tightness but couldn't get it going so he called the AA and I left

I found out later that the AA guy solved the problem by taking the battery connections off and cleaning them and the terminals my mate said the AA guy had shown him some crud on the vattery terminal and this was enough to stop the car firing up

So that's one mistake I did learn from (pity about the rest)
Nigel Atkins

Just seen on other forum that the B drive has resolved his starting problem - it was an earth strap

Now we're trying to convince him to replace the worn braided strap even tho' he's cleaned it up

Sometimes (quite often in fact) it is the simple solutions - but not always
Nigel Atkins

Nige there are probably a dozen great reasons why a starter motor will not start an engine.

The hard part on a BBS like this one is to actually have an accurate description of the real problem

With such a description the solution is easy to assess. :)

Mind it gives us all something to chat about in our sad little lives :(
Robert (Bob) Midget Turbo

I told him to swap the earth lead Nige

he doesn't seem convinced yet does he?

All for about a fiver at his local spares shop, never mind

I'm about to leave him to it, seems he thinks things can only get better

(still he did clean off the corossion on the tags)
Bill 1

Hi Guys, Here is the latest on what is going on with my Midget. I have changed the solonoid on my car. I was able to crank the engine over for a few seconds at a time a couple of times in a row . THen I would try again and it would not turn over at all. I think I can hear the solonoid clicking when I turn the key. Any helpful tips on what to check next?
Thanks,
Leonard
lm Mayor

Bill !! hey (hey) yes, £6 for the actual correct one and his cleaning efforts didn't seem that thorough on the mounting block or solonoid but we don't know the full circumstances he might have been under his car outside in dreadful weather
(talking about the B owner above)

Bob, Leonard,

I'm a very simple type (as Bill can testify to) so I can only understand simple things

but starting with the simple and obvious is usually a good place to start rather than "when all else fails check the bleeding obvious"

clicking could be not enough power getting thro' such as flat battery (but not this time)

or bad /poor earth or other connections

or as Bob rightly says it could be many other things

I can only go on what experiences I can remember from my various ownerships as I have so little mechanical knowledge or appitude

Not sure whether Bob'll like or believe this next bit :) -

here's one that's caught me out twice with my existing Midget

clicked by didn't start - reason - HT ignition lead from dissy cap to coil was not fully seated but I couldn't see that as the overtight rubber cover cap concealed this

I regularly check my leads for tight secure fit but as the cap on the coil lead end was overtight as I pushed it on further the vacuum created inside was pulling the lead connection out of the coil slightly

It was only after the second failure to start I remember that when the leads were new this cap cover being overtight need burping like a tupperware lid
Nigel Atkins

Leonard

That is better more info
However still not given any history, has this developed, has it always occured erc. etc.

OK if you can hear the solenoid clicking yet nothing happening (not in the original post) then we can go further

Bad earth: check that there is an earth strap from the engine/gearbox to the car bodywork. On my car I have one "actross" the engine mount thus connecting the engine to the bodywork across the rubber joint. If you have some heavy duty jump leads then placing one from the negative of the battery to the engine will test the same thing. Normally if this is the problem you will "fry" the throttle and choke cables trying to start the car I note no mention of this.

Sometimes the engine can become very stiff, if it has been laid up for a long time? Have you had the car started? Perhaps you can push it off?

Lazy starter motor. Again who knows but if everything is fine then it will eventually become the reason.

What I am really curious about was your original statement
""The problem I am now having ( and have always had) is that when I turn the key the starter motor will engage for perhaps 1/4 of a second and then dissengage not allowing me to start the car. When the motor dissengages I get a " hmmm" sound until I turn back the key and then try again to most times get the same thing over again""
This sounds like a totally different problem to what you are now describing. Has something changed?

Nige, :)

If you went to a doctor and said from time to time I feel dissy and he went about the task of changing your heart, then your lungs, then gave you a couple of new ears, before realising you were a deckhand on a ferry but suffered from sea sickness you would consider him stupid wouldn't we. LOL.
My wife hates breaking down and having to ring me, she thinks it is the spanish inquisition! LOL
Bob Turbo Midget England

..bet she doesn't expect that, Bob!
David Cox

Inquisition it may be, but Bob is right - it is very difficult to give a proper diagnosis with partial or inaccurate descriptions of what is happening.

The original fault description of "engaging for 1/4 second, then disengaging" seems to mean that the starter sometimes spins enough to engage the bendix, but barely turns the engine. The other reference to the starter "humming" is when it fails to engage the bendix and simply spins the starter motor which then hums.

The fact that the solenoid is clicking suggests that it is OK and working as it should. The fault is "downstream" of that.

Either: Connections in the the cable between solenoid and starter motor or in the other "feed" route to the starter which is the battery - negative cable to earth - earth strap to engine.
Or: Faulty starter motor (worn brushes)
Or: Sticking bendix.


Guy Oneandahalf Sprites

Well, this is getting very frustrating; new starter motor, charged battery , new solonoid, checked all connections, even tried connecting a booster cable to engine and grounding the other end to car frame to get a good ground and still here I sit with nothing but a clicking solonoid when I turn the key.Engine does not turn over at all. Time to take a break from this for today.....:(
lm Mayor

Im,
Start by testing the motor off the car, but still using the solenoid and car wiring. Just unbolt the starter motor
Guy Oneandahalf Sprites

Leonard as Guys says but please have you ever had the car running? can you start the car with a push?
Robert (Bob) Midget Turbo

Bob, can you give me this doctor's number please I quite often feel dissy and could do with a new shoulder and elbow

You're quite right about needing to ask the right questions to get a fuller understanding but I for one struggle to describe problems and symptoms as I’ve not got the necessary knowledge or vocabulary

The changing of the earth strap that Bill and I were writing about is on another car (and forum), I should have made this clearer, it was used as an illustration of one type of thing to first check thoroughly and then change if required

I don’t think I (or Bill) have suggested, to Leonard or anyone else, changing anything without checking it’s condition first, with the B owner’s earth strap we were trying to point out that he may have resolved the problem at present but he’d also prevent the same problem reoccurring by replacing the cleaned, but worn, braided strap with an insulated (correct in that case) version because of it’s location under the car - again it might have been confusing here

Another difficulty of not being actually there with Leonard is you can’t see (and no disrespect meant to Leonard, none of us are born knowing we all have to learn) whether Leonard knows or is doing the checks correctly (not that I would necessarily know)

Guy’s suggested starting at one end and given the results of this you guys can lead Leonard back to the next thing to check and so on

Bob what did you think of my unseated coil lead, probably never hear of it again but as it’s a very simple thing to check (therefore even I can do it) and only takes seconds if my current Midget ever clicks again without starting I will now remember to at least check

Again the coil lead seating was just one rare example of simple things that prevent a car from starting – like dirty and badly connected earth leads :)
Nigel Atkins

Hi Nige

Personally I don't give a hoot how many things helpful people like yourself and Bill ask members to change in an attempt to rectify a problem.

On a BBS such as this when someone asks a question they are bombarded with suggestions as wierd and wonderful as someone suggesting I should enter X Factor !!! :)

I am pleased only if the advice I give is sound, and so long as the member gets his/her problem cured then fair play to everyone involved.

This case was slightly different and has caused some confusion by poor old Leonard not understanding what the fault actually was. My only concern on this thread as always, is to understand EXACTLY what is happening to Leonard's starter and to give him the best advice I possibly can. :)

On my own cars I only change things when I know they are faulty rightly or wrongly that I believe is the best way to ensure my car is always reliable. Changing parts indiscriminantly is a recipe for disaster IMO

To that end in 40 years I can only remember ever changing 1 condenser! LOL
Robert (Bob) Midget Turbo

Leonard,
You say you have checked all connections but have you disconnected and cleaned them all?

Also if it is an earthing problem do as Bob suggests and connect a jump lead to the battery terminal not the bodywork as you have done, because by connecting to the body proves nothing if the battery earth lead/connection is faulty.

If you do as Guy suggests and remove the starter, whilst it is out you can also check James original idea of missing teeth on the starter ring by shining a light in the hole and turning the engine over by hand.

Trev
T Mason

Good call Trev and made clear (unlike my posts)

Bob, you and your condensers - you should take them on X-Factor(ies)

I bet you love flow diagrams :)

I understand what you mean and I think (in our different directions) we are in agreement

I don't think I (or Bill) have ever suggested changing parts indiscriminately, changing a part that is working at the moment but is likely to be unreliable in an unreasonable time, yes

Then we enter the realms of faulty new parts and components that can easily catch out those who have not suffered by this before

I think it’s difficult, over a BBS, for a novice to give the correct information for a more expert person to understand exactly what is happening

From Leonard’s OP -

>>...when I turn the key the starter motor will engage for perhaps 1/4 of a second and then disengage not allowing me to start the car When the motor disengages I get a " hmmm" sound until I turn back the key…<<

this would often, but not always, happen to me on first attempt of starting the car with on my old starter motor, the car would always start on second turn so this was usual for my car but as my car is a daily and I have a pet hate of cars not starting (and being unreliable) I replaced the starter for a modern hi-torque to be more reliable and save battery power particularly for the winter

and of course to relive that pet hate
Nigel Atkins

Hi Guys, thanks for the additional info; I will try out grounding the car again using the battery AND all the other tips you all have given me. YES Bob I was able to get the car running when I was at the stage where the starter motor would turn the engine briefly but of course need more reliability if I am to feel comfortable taking the car out of my driveway and have to restart it. I may well be able to start the car by pushing it and popping the clutch but have not tried this. As I stated now ( currently) the starter motor is not engaging or functioning at all.I guess I can also take a tester to see where the power is making it to to see if the power is even going to the starter. Doing my best to describe what is going on and appreciate all the help.
lm Mayor

Has anyone asked you to check that the battery is fully charged and holds a good charge?
Daniel Thirteen-Twelve

I highly recommend a gear-reduction (sometimes called ‘high torque’) starter. I installed one in my 1967, and while pricey, it has none of the problems that the original unit has. It won’t disengage til you want it to and draws less current. Also, it pushes the drive gear into the flywheel rather than pulling it from the rear, so if your teeth are worn aft, you’ll get many more miles of use before having to replace the ring gear on the flywheel (a real hassle).

Also, you can either use the selenoid mounted near the firewall or the internal unit—or save the latter for a back-up, should the external ever fail miles from home.

Finally, the Nippendenso motor will outlast the original and is cheap and easy to replace, without having to replace the gear reduction housing. Only trick in mounting is figuring out which orientation is best, as the housing may be adjusted by removing the allen screws that attach it to the motor. Easy to do. Just use index marks with a Sharpie, and you’ll get it right in a couple of tries.

Joel.
JM Young

Daniel - in OP >>The battery is fully charged so this is not my problem<< but good point about it remaining so

I should have put a question mark on the end of this >>clicking could be not enough power getting thro' such as flat battery (but not this time)<<

Joel - a new starter has already been installed (I'm a hi-torque fan too)

Leonard is checking to see if suffient supply is reaching his various new parts which he elected to fit

Just realised Dr. Bob might not have been not have meant me or Bill - I may have misread (again)
Nigel Atkins

This thread was discussed between 20/10/2010 and 24/10/2010

MG Midget and Sprite Technical index

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