Signs of starter going bad?

[JHZR2]

91 BMW 318i, always started fine. Recently instead of a constant sound when cranking (car has always turned over four times then catches on the fifth since I've owned it, and has been perfectly reliable), it seems like on one of the fires, it skips, almost like it misses a tooth or something.

So instead of

Raaar-raar-raar-raar-idle

It seems to be

Raaar-raar-ra-click-raar-idle

The click isn't like when a starter is stuck or a battery is weak and a solenoid clicks. In fact, click may not be the right sound. But one of the clicks seems to be faster/shorter than the others.

Starts just fine, runs just fine, comfortable driving it anywhere anytime. But this noise has me worried if the starter gears have a broken gear tooth or something that makes part of the crank short or fast and abnormal,

Maybe it's totally nothing, or maybe its just a slightly weak battery, don't know. But some general insight would be appreciated.

Thanks!

 

[spasm3]

Not familiar with BMW but could the bendix be weak and not fully engaging the flywheel? It might skip a tooth doing that.

 

[Quest]

sounds like your commutator is worn..causing intermittent contact.

This is fairly common as starter ages....machining might give it a few more years of life but mot much.

I'd replace it with a fresh new reman if I were you.

Q.

 

[crazyoildude]

check it out before the flywheel gets damaged

 

[bullwinkle]

Never had a BMW, but I've had (older) GM starters that did that when shimmed too far away from the flywheel, or the starter gear was wearing. Hopefully not the flywheel/ring gear.

 

[KB2008X]

I would be concerned with the starter motor and the flywheel. Continuing to operate the starter motor with possible gear teeth issues or engagement issues and/or flywheel teeth problems may eventually cause damage to one or the other, or both. You don't want to be replacing the flywheel.

However, do yourself a big favor and replace the battery with a known good one. You'd be amazed how many times I've seen people spend hundreds of dollars and countless hours chasing some gremlin in the starting system and it was a bad battery. So, just do it. Then re-evaluate the situation.

 

[JHZR2]

Thanks all!

What is the best way to check the flywheel contact?

Beyond that, I know the battery was somewhat weak, as the car had sat for a while (2 weeks?), and the battery does seem to have a slow loss. But checking the other stuff is important. I doubt its very hard to pull the starter on this car.

Thanks!

 

[Warstud]

Just go ahead and replace the starter yourself before you end up stranded some where and have to waste a $100 to have it towed. The longer it takes to turn over....the more stress your putting on the alternator and battery.

 

[eljefino]

Should be a flywheel inspection cover you can pull easily. The flywheel will rust where it isn't touched daily by that gear.

 

[JHZR2]

Originally Posted By: Warstud
Just go ahead and replace the starter yourself before you end up stranded some where and have to waste a $100 to have it towed. The longer it takes to turn over....the more stress your putting on the alternator and battery.


I have AAA

And it cranks the same number of times and catches at the exact same point that it ever has, no change whatsoever. Just a noise difference I noticed...

 

[JHZR2]

Originally Posted By: eljefino
Should be a flywheel inspection cover you can pull easily. The flywheel will rust where it isn't touched daily by that gear.


But there are LOTS more teeth on a flywheel than on the gear on the starter, right? So each time the two spots will touch on different spots, right? So that wouldnt happen...

 

[SteveSRT8]

Diagnosis and repair are tricky and unlikely to be done effectively over the Internet.

The starter/battery/alternator triumvirate is a difficult trio to diagnose sometimes. That's why they make a handy machine for it.

Almost any auto parts place can 'hook' you up and help in figuring out exactly what to repair!

 

[KB2008X]

Again, do yourself a huge favor and swap in a known good battery, before buying anything.

Pulling the starter and checking the teeth and engagement mechanism and spinning the engine and checking the flywheel with the starter out is "free" and hard to argue against, but there can be problems with one or more of the starting system components that you just may not be able to see. So doing that may or may not yield results.

When diagnosing the starting system for a problem that is not obvious you need to eliminate the battery as the source of trouble first. Always.

I'm not advocating for the purchase of a battery, just the temporary replacement of it. You can get the present battery tested, but even if it tests good it doesn't unequivocally mean that it is. The only way to clear the battery as a suspect is to remove it from the system and retest the system. If you get the exact same result with the "new" battery as you did with the old battery you then know for a fact that it is not the problem and you can move on to the next logical suspect.

The suggestion to get the system tested is not a bad one. I personally don't put a lot of stock in having someone else do my diagnosing, but that's me. It would however, be better than diagnosis by internet.

Dealing with facts will lead you to a solution much sooner than futzin' around with woulda, coulda, shoulda and maybes.

 

[JHZR2]

Makes good sense. Totally agree on taking the battery out of the scenario and going from there. Easy enough. Will keep on top of this. Appreciate the advice!

 

[Artem]

Any sort if starting problems should quickly raise a red flag and a full inspection should be a top priority. Having the battery and alternator checked is FREE at Autozone (and I'm sure other places, I'm just speaking from experience). If those check out fine, proceed from there.

You could mistakenly replace the starter and still experience the same issue because of a fuel or spark plug problem....