MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - Starter engages - starter doesn't engage

I'm having a starter problem. I have a 4 year old gear reduction starter on my 67 GT.

Yesterday for the first time it didn't engage when I turned on the key. All other electrics worked fine. Car has a new wiring loom.

Car had started earlier and was fully warmed up. I took a stick and tapped the starter and it fired up right away again.

This morning (freezing) same thing. Wouldn't start, tapped starter, fired right up.

Is this the starter beginning to go south, or an electrical issue?

Bernie
Bernie Lowe

Bernie, It could be a poor connection at the starter. But I suspect that the solonoid is hanging up and when you tap it the solonoid frees up and performs normally. I have a '67 with a '68 starter on it and it has been working flawlessly for 25 years. Check your battery connections and the engine ground strap. Also check the battery voltage when cold as well as when the car is running. How old is the battery (s). RAY
RAY

Bemie,it is in fact an old road service trick shown to me by an old tow truck driver 40 years ago, he used a special tool he reffered to as the "BFH" of course that was in the day before lightweight starters with lightweight magnets[read easily broken] without a doubt if you can bang on the starter to make it spin you need a starter.
As a related aside I am reminded of a friend from school who like most of us in the 60s was broke most of the time,when shown that a tap on the starter of his VW Bug would bring it to life,he took it to an art form by hanging a hammer from the body of the V-dub right near the starter with a rope from the hammer to the window nearest the driver.SOoooo,when he wanted to start his car he pulled on the rope,banged the starter,turned the key and was on his way.
You could try the same thing but a new starter might serve you better. RIC
RIC LLOYD

Thanks for your suggestions Ric & Ray. When the temperature rises above 6 degrees fahrenheit (right now), I'll try your fixes - well maybe not the hammer from a rope thing - too old for that. Bernie
Bernie Lowe

What do you mean by 'didn't engage'? Did the starter spin but not crank the engine? Or didn't the starter even spin?

These are pre-engaged starters which means the pinion *should* be engaged before the solenoid contacts close to energise the starter. If the solenoid or pinion were jamming, which does seem to be the case if tapping it cleared it, then the starter shouldn't have spun either. If the starter *did* spin but didn't turn the engine then I'd suspect you have an incorrect starter which is perhaps only just engaging with the flywheel at best, and sometimes not at all.

In any case tapping to free a stuck starter is something that would only have been necessary on an original Lucas unit after quite some years and miles, I would not be impressed if I started getting problems on a unit that was only 4 years old. How many miles has it done?

I was pencilling in a gear-reduction unit the next time I have to change a starter as they reduce the load on the battery so much. Don't say that is going to go the same way as the ball-bearing release-bearing, electronic ignition, pointless fuel pump and telescopic dampers i.e. into the bin marked 'nice idea, pity it didn't work'.
Paul Hunt

Paul - the starter didn't even spin. It felt like there was no current, not even a click when I turned the key. That's why I need to to check all electrical connections to the battery & starter first, to make sure that everything is properly connected.

The new starter only has something like 10K on it. I hope the problem is electrical!
Bernie
Bernie Lowe

A lot of these starters are Nippondensos. If it is one of these, you can fix it for another 4 years or so cheap and easy. Go to ebay and look up solenoid contacts or a similar search. One contact gets a step worn on it, and it doesn't make the grade. You buy a set of both contacts (one may be different than the other)and install them easily.

You can search Google or whatever and find pics and instructions.

The fastest way is to take it apart and braze the contacts back to thicker than needed, then grind them down to the same thickness. Reassemble, and you're done.

I read about a guy that soldered pennies to the contacts, but I'd not recommend that, even if it could work for a while.

Or take it to a good motor guy, they've seen them before and probably have the replacement contacts. Our local Chrysler service has them for $5, if you know the right guy to ask.

If it's a Bosch, maybe a new solenoid. I couldn't get the screws loose on mine, so got a new starter, then a rebuilt, then another and another. Denso's are better, IMHO. You could even carry spare contacts with you, only an ounce or so.
Tom

If you got no sound at all from the solenoid then maybe the ignition switch wasn't powering it, and tapping it getting it going next time was either a co-incidence or a bad connection in the white/red at the solenoid. In this case there would be no dimming at all of the ignition warning light, whereas if the solenoid *was* being powered but was jammed in position as so not making any noise, the warning light would dim very slightly. You should certainly be able to see this dimming on a digital voltmeter connected between the white at the fusebox and a good ground. 4 years and 10k is very low usage in my book, especially for a generic Denso which are used in many modern cars these days, AFAIK.
Paul Hunt

I agree, Paul. They should last a long time with new contacts. Another thing I've seen about these starters is that they ship with the adapters in place, bit not tightened all the way. One poster said his adapter came loose. I suspect it may have not been tight from the beginning. As users may "clock" the unit to their application, the seller may assume you will check this. But we're used to getting parts and just putting them on, hard to blame the end user.

The first engine I built, when I was 16, was a VW. I had only a couple of tools, but I was determined. I ordered a kit with new crank, rods, pistons, buckets. I assembled it all OK except years later I learned that I hadn't checked the rod bolts. The crank, rods, and bearings came as an assembly, and I "assumed" it was ready to just slip into place. The engine lasted a long time in VW years, but I heard from the VW shop later that the rod bolts hadn't been torqued right. Whoops! I asked a friend of the guy that bought the car if he knew about this, and he said "Oh, don't worry about it, he drove that thing like a formula one racer." I still feel bad about it, tho. One of those things you wish you could redo in your life.

Thinking back, there are soo many other things like that which could have happened, but didn't. I've been blessed.
Tom

My starter came loose from the adapter so it may be my post you are thinking of. However that just had two piddly self-tappers and a bit of super-glue holding them together. It's fortunate that the action of the pinion on the flywheel pulls the starter towards the engine back-plate and doesn't push it away from it other wsie it could have been pushed out altogether. As it was I was horrified to see the starter hanging at an angle only a couple of days after I had fitted it because the self-tappers had pulled out, presumably just from the weight of the starter hanging on them! Needless to say it went back and I fitted an original Lucas type. My supplier assures me that new stock have through-bolts and so shouldn't suffer from that problem. Maybe in another 30 years...
Paul Hunt

Bernie. I had the same problem, a few weeks ago, with a factory starter. The main starter terminal connection had loosened, about one half turn, and that was sufficient to give me no fuel pump sound (on initial turn of the key), no red light for the charging system and no starter. When the nut was tightened, I leaned over the side of the car, turned the key to see if the starter would engage and the engine started immediately. My first instance of a loose main terminal nut being the only cause of a starting problem. But, the car has been running fine since then, so that must have been the proximate cause.

Other causes have been bad battery terminal to battery terminal clamp contact (clean, tighten), bad battery terminal clamp to cable contact (do not use the type of clamp having the cross strap to slip the cable into--use a molded on clamp) and the cable being internally corroded (replace cable).

Thus, I agree that the first thing you need to do is to clean and inspect all of the electrical connections before doing anything else. Problems with the battery to starter connections can be checked by using a volt meter attached to the main starter terminal and a ground. You should see battery voltage when connected. When the ignition switch is turned to the "start" position, you should see 11.5-12.5 volts present at the starter. If not, you need to find out where the problem is before worrying about the starter condition.

Les
Les Bengtson

Ray, I didn't know you could put a 68 starter in a 66. Seems like a good choice if you can as the 68 I believe is the pre-engaged type not the inertial type that tears up ring gears.

I thought the pinion gear count was different between the two since in 1968 they went to a bigger ring gear/flywheel.
Robert McCoy

Robert, Unfortunatly it is not a straight swap. I had access to parts from a '68 GT that had been dismantled. I used the engine backplate, flywheel and starter motor. Since the engine was out of my car at the time it seemed to be a wise upgrade. The ineritia starters were trouble prone in that they beat up the flywheel when engaging and frequently would jam their teeth with the flywheel. On the distributor end of the starter there is a small extension cover. If you remove this cover you will see a square shaft. This was designed to be used to back off the starter from the flywheel if the two should jam together. This happened to me the first day I owned my car in 1972. I thought that the engine had siezed up! The dealership,where I had purchased the car,sent out a mechanic and , much to my amazement,he reached under the hood with a 1/2" wrench and freed the starter. It then started up and did so 99% of the time. However, after that episode I always carried a 1/2" wrench in the boot. That starter from the '68 GT has never been apart since I installed it and still works great today. RAY
RAY

The inertia starter has a 9 tooth pinion, the pre-engaged for the 4-cylinder has 10. Ironically the V8 also has 9 even though it is a pre-engaged.

9-tooth geared starters are a straight swap for the inertia even though they are pre-engaged.

Rocking the car in 4th is the usual and easier method of freeing a stuck inertia starter. I had one start to stick in a Mini many years ago. The manual called for scrupulous cleaning and no lubrication, so that is what I did, only for it to stick again after a short time. Did it again, and it started doing it again after an even shorter time. Then an eminense gris said "put a smear of light oil on the spiral gear" and had no more trouble with it after that.
Paul Hunt

Paul/Ray, thanks. I suspected you changed something else Ray but had to ask. I've done the rocking several times. Replaced the ring gear a long time ago as it was pretty chewed up and engine was out. Only one jamb in 10 years.
Robert McCoy

This same problem was common on Fords of the '60s. The problem was that overnight the dew would cause just enough rust on the stator that it wouldn't crank over the engine. A whack with a hammer was enough to loosen the rust thus starting the car.
S.L. LaPaugh

This thread was discussed between 16/01/2009 and 22/01/2009

MG MGB Technical index

This thread is from the archives. Join the live MG MGB Technical BBS now