Morris Minor Owners Club

I might be having a total brainfade here - so pls tell me if I'm stupid

I think the starter on the parts car I just brought is spinning the wrong way.

Pull the starter - starter motor spins - no engaging on the flywheel. The engine turns fine on the crank handle.

Generator/battery were removed, so I don't know if it was converted from +ve earth

Have tried two starters motors now and both do the same thing. The teeth look (feel) to be ok on the flyweel. The first starter had badly worn teeth, but behaved the same way. The inertia mechanisms seem to be ok (free and smooth) on both.

If the polarity is wrong, wouldn't the starter spin the wrong way?

No, it spins the same way, +ve or -ve earth.
Are you sure it's spinning the wrong way ? It might be a sticky shaft preventing the gear from throwing out.

I not sure it is spinning the wrong way.
It is definitely spinning.

I cleaned and oiled the bendix thing before I fitted it and it was smooth running.

Will remove this motor tomorrow and bench test it.

Failing that it's back to the crank handle.

iirc, you're not meant to oil the bendix...

It causes it to stick.

I might be wrong, but I have a feeling that's the case. Someone with a memory'll be along in a moment to say

Pyoor_Kate wrote:iirc, you're not meant to oil the bendix...

It causes it to stick.

I might be wrong, but I have a feeling that's the case. Someone with a memory'll be along in a moment to say

It will do eventually as the dirt/dust sticks to the oil, but it won't affect it straight away

Pyoor_Kate wrote:iirc, you're not meant to oil the bendix...
It causes it to stick.
I might be wrong, but I have a feeling that's the case. Someone with a memory'll be along in a moment to say

oops - didn't know that.

In any case, this engine will be coming out of the car soon. I want to get it running to do a compression test on it first.

I had a friend at work who had a Skoda Estelle, and swore this happened. One day it went round the right way, then the next the wrong way. Don't believe it myself.

If the starter had come off another car that went round the other way (are there any?) then that might explain it.

The oil on the bendix can cause sticking because it collects dirt and goes sticky. Graphite is a good lubricant becauseit's dry.

Ok, further update.

Working with the best of my spare starters, I fited it up to my spare engine and gearbox. Testing it both positive and negative earth it worked fine and cranked the spare engine well.

Refitted it to the parts car again - still same results as earlier.

Assuming it's spinning the right way, and that the bendix is working fine, and teeth are not too worn; why wouldn't it engage the flywheel?

It is an early 948 engine APJM (early type angine #) - was there a difference in the starters?

W

Hello Shawn,

you will need to do some measuring with the starter out, distance of ring gear to front of engine back plate, and compare with the starter pinion when extended.
I agree that an oiled pinion will work initially so that shouldn't be the problem. Also ensure that the battery is well charged as it may be that it has enough to spin the starter but not 'lively' enough to throw out the pinion.
Strange one.

Alec

My 54 did this when I'd first got to the MOT station
I needed a push to get going again and it's not done it since.

One possibility I can imagine is poor connections on the big wires! This can cause a major drop in available power at the starter, therefore it won't get enough of a 'kick' to throw the starter gear along the bendix into the flywheel....
Just a guess, but try it with jump leads off the car - if that works then then try it with jump leads on the car (use both leads as it may be the supply or ground that are high resistance).

On my 54 I'd not tightened the battery terminals for the first outing (severe lack of time and I was too late for the first MOT anyway ).

I would imagine that the teeth on the flywheel starter ring have
worn away! These usually wear in one of two positions so that
you can finish up with good teeth all the way round except in
the areas where it matters! It is possible to view t he teeth
through the hole when the starter has been removed (turn it
via the starting handle) and it is also easy to check the rotation
of the starter.....it should rotate anti-clockwise when viewed from
the 'starter lead' end. You can verify this by observing the end of
the shaft without removing the starter. ( it is simple to check
for a bad area on the flywheel teeth by rotating the engine via
the starting handle say a quarter turn and then see if the starter
works). Since the same starter works on your spare engine it
would suggest that either the flywheel is too far away from the
backplate so that the bendix cannot reach it or the backplate itself
is 'the wrong one' i.e. the starter motor mounting holes could be
1/2" further away from the flywheel ring so that it works perfectly
but cannot engage. Since you have the two engines at least you
can compare measurements.

it is also easy to check the rotation
of the starter.....it should rotate anti-clockwise when viewed from
the 'starter lead' end. You can verify this by observing the end of
the shaft without removing the starter.

why did no-one else suggest that... Simple is best ;-)

lowedb wrote: If the starter had come off another car that went round the other way (are there any?) then that might explain it.

Yep, Triumph 1300 has the starter at the front of the engine, and it spins in the opposite direction to the norm. But the bendix is also oppostite threaded (obviously, or it wouldn't chuck out!). They're also rare as rocking horse poo, so I doubt that's going to be the case!

Could well be ring gear teeth missing, if it's spinning well enough and works on another engine - Try turning the engine by hand a few degrees. Or better yet, try using the starting handle if there's enough bodywark to stop it flying facewards if anyting slips or goes wrong!

rayofleamington wrote: ...One possibility I can imagine is poor connections on the big wires! This can cause a major drop in available power at the starter, therefore it won't get enough of a 'kick' to throw the starter gear along the bendix into the flywheel....

You were right, Ray.

Earth strap under car disconnected. - Cranking fine now.

One day I will learn to check the obvious things first.

Thanks all!

RAY... nice one, another example of 'think simple'

Shawn wrote:Earth strap under car disconnected.

Lucky the smoke didn't escape from the choke cable.