Technical Starter whirs but doesn't engage

[Noah500]

So... I used the car on Sunday (80 mile round trip to Brooklands), everything OK except it sounded like the exhaust was blowing a bit - I fairly recently replaced the exhaust and I thought I may have not put enough gasket sealant on the manifold connection. I unbolted the exhaust, re-gasketed the exhaust and left it 24 hours.

Today I went to test the car to see if it was still blowing, turned on the ignition, gave it a little choke and pulled on the starter lever - sound of whirring from the back but engine didn't turn. Left the key on, went round to the engine bay and pulled the starter cable manually - same result, though it sounds a bit like there is a slight clicking, as though the teeth are clipping the flywheel but not engaging enough to turn it.

Any ideas? Could I have nudged something out of alignment while reaching round to the front exhaust connection?

 

[bugsymike]

So... I used the car on Sunday (80 mile round trip to Brooklands), everything OK except it sounded like the exhaust was blowing a bit - I fairly recently replaced the exhaust and I thought I may have not put enough gasket sealant on the manifold connection. I unbolted the exhaust, re-gasketed the exhaust and left it 24 hours.

Today I went to test the car to see if it was still blowing, turned on the ignition, gave it a little choke and pulled on the starter lever - sound of whirring from the back but engine didn't turn. Left the key on, went round to the engine bay and pulled the starter cable manually - same result, though it sounds a bit like there is a slight clicking, as though the teeth are clipping the flywheel but not engaging enough to turn it.

Any ideas? Could I have nudged something out of alignment while reaching round to the front exhaust connection?

Check for flat/duff battery first.

 

[Noah500]

Pretty sure it's not the battery as the starter is turning - or something's happening, at least - and the lights work, and dim slightly when pulling the starter lever, so power's definitely getting to the starter.

A video may help

 

[bugsymike]

I agree, sounds like you need to take the starter out, check for tooth damage on flywheel as well as starter gear, but also sometimes the one way sprag/clutch on starter gear, I have had the gear slipping however usually that makes more of a high pitched squeal.

 

[Goldnrust]

Unless the starter itself is very loose, there's no way it cam come out of alignment or any thing like that.

There's one final test you might do, and thats to turn the engine over by hand a little (either man handling the pulley or put the car in gear and push the car a little), they try the starter again. That might eliminate the idea of damaged teeth on the flywheel, by moving to a different part of the flywheel.

But from the sound of the video it sounds like something inside the starter has broken to me, it's clearly spinning and when it slows there's a rattling sound. I think the only sensible route forward is to remove the starter and take a look.

 

[Noah500]

Ok, I tried moving the car in gear a bit 0 same result I also gave the starter a few judicious whacks with a rubber mallet... still no joy.

I'll take the starter out and have a look, as suggested

 

[Noah500]

Is it just those 2 nuts on the left (after disconnecting the battery)?

 

[Goldnrust]

That's probably for the best that it didn't help, changing a starter is a lot easier than changing a damaged flywheel!

Those two nuts, and one on the far side of the starter, level with the lower nut on this side (if that makes sense!)

 

[RHDGiardi]

Is it just those 2 nuts on the left (after disconnecting the batte

Is it just those 2 nuts on the left (after disconnecting the battery)?

There's probably a third nut on the other side. Take the motor out, and on the bench connect it to a battery, body to earth, then watch what happens when you pull the lever. The pinion should move up to the outer end of the shaft and spin round very fast. If it doesn't move virtually to the end, the lever isn't doing it's job. If it does, then you need to check that the pinion is still connected to the starter motor itself, or is just spinning around uselessly. To do this, I think I'd use a piece of wood against the pinion, then pull the lever. Be careful though, maybe wear eye protection, as, if it's working properly, the force of the rotation should flick the piece of wood out of your fingers, but if the starter's duff, the pinion won't move.

If all seems ok after those tests, but it still doesn't work on the car, it suggests insufficient voltage is getting to the the motor.

 

[Noah500]

Thanks for the tips. I'll take the starter out and check it once I have some time.

 

[the hobbler]

Thanks for the tips. I'll take the starter out and check it once I have some time.

Yes, there is definately a 3rdnut the other side of the starter. Don't forget to dis-connect the battery prior to working to take the starter out

 

[Noah500]

Ok, got the starter out yesterday and took a look. The switch seems to be ok (as evidenced anyway by the fact that the motor turns) but I cleaned it up. Will do a bench test with a battery just to double check.

The teeth on the Bendix are a bit worn but not too bad, at least compared with the example in this video I found:

The Bendix is not moving unduly in the bush. Teeth on the flywheel also seem to be OK.

However, the problem appears to be that, although the Bendix slides back and forward on the shaft OK, when I pull the lever the Bendix doesn't move, therefore would not engage with the flywheel.

Next step is to take it apart and check the back end of the lever.

Since I've got the starter out, I may replace the Bendix, bushes and brushes anyway, as they don't seem to be too expensive

 

[bugsymike]

Sounds like a good idea, the brushes and commutator may be bad preventing starter from spinning correctly.
Also the lever operated solenoid contacts may be worn, I had a Peugeot 504 diesel that did similar due to the copper contacts inside the solenoid and I was able to turn the copper bar over to an unworn /clean section and clean the two contact posts to solve the problem.
The principle is the same whether it is cable operated or electro magnet solenoid, it still has to make a high amperage connection.

 

[Noah500]

Lever is broken... that would do it!!

 

[Goldnrust]

Yes, I think you've found the problem there! The poor car must have had some seriously over zealous pulling on the starter lever in the past to have stressed that enough to break it!

 

[bugsymike]

Still no doubt you will check the whole starter whilst stripped as extra pressure may have been needed to make the connection due to general wear.

 

[Toshi 975]

When I rebuilt a number of starters last year I put together a couple of extra what I called auxiliary rebuild kits which contain new heat shrink insulators, all stainless steel fixings and a new thrust washer. Still have a couple of kits left if you are doing a posh job.

 

[Noah500]

When I rebuilt a number of starters last year I put together a couple of extra what I called auxiliary rebuild kits which contain new heat shrink insulators, all stainless steel fixings and a new thrust washer. Still have a couple of kits left if you are doing a posh job.
View attachment 427396

Is this just replacements for the existing nuts and bolts etc.? Where does the heat shrink go?

 

[Toshi 975]

Yes the correct pattern fixings but new in stainless steel, a new thrust washer for the brush end of the armature as they can wear away and the heat shrink replaces missing or damaged insulation on the long bolts that hold the starter together with an extra piece as the insulation can get damaged where the field coil connects to the brushes.

Is this just replacements for the existing nuts and bolts etc.? Where does the heat shrink go?

 

[Noah500]

Ah, ok... Doesn't seem essential but looks quite nice. How much?