Advice pls - Intermitant mechanincal noise

[MPoxon]

Evening all,

I'll try and keep this a brief as possible but following the issue I had with the solenoid not disengaging on my starter motor. I purchased a Hi-Torque heavy duty starter motor from a TVR specialist as this looked to address the issue with the solenoid position and give a little more power for those cold morning starts.

I had this fitted on Friday. The first issue was the that exciter wire did not have enough current to engage the starter 12v when disconnected but dipped to 6v with starter connected. I am (supposed to be) off to Gaydon tomorrow so I got a temporary switch wired in to feed to starter straight from 12v. This worked fine.

Cleaned the car ready for Gaydon today, stared her up for a quick run around the block and to get some fuel and I now have a mechanical sound which is intermittent. It happens when you start the car and then goes away then you get in to drive off and then as soon I put my foot on the clutch it comes back again. It stands to reason that is it starter motor related but that would mean it would be engaging and disengaging which does not sound likely.

Here are two videos.... any advice would be greatly appreciated as always.

Engine running with noise, then no noise:
http://www.youtube.com/watch?v=9uoTVZzhK_c

Engine running with noise, then turned off.
http://www.youtube.com/watch?v=GRhAwREl7Gc

So far not looking good for Gaydon. Typical seeing as the weather looks to be great

Matthew

[Aussie John]

Is the original wire to the solenoid [ the thin one to the operating coil] still connected with the new 12V supply connected to it? If it is then maybe there is some voltage on the original wire all the time which is trying to bring in the pinion. This could be caused by maybe a faulty relay in the immobiliser circuit. Good luck! PS remove the original wire if connected and see if the noise has gone.

Edited by Aussie John on Saturday 25th June 21:22

[Ribol]

Are you saying the noise is always there if the engine is running and you have the clutch depressed?

Does the clutch feel the same as it usually does, any pedal vibration etc?

[MPoxon]

Aussie John]Is the original wire to the solenoid [ the thin one to the operating coil said:

still connected with the new 12V supply connected to it? If it is then maybe there is some voltage on the original wire all the time which is trying to bring in the pinion. This could be caused by maybe a faulty relay in the immobiliser circuit. Good luck! PS remove the original wire if connected and see if the noise has gone.

I am fairly sure it has been disconnected to make way for the new temporary bypass circuit but I shall check tomorrow. Could be a good shout though it would stand to reason, thanks for the suggestion.

[MPoxon]

Ribol said:

Are you saying the noise is always there if the engine is running and you have the clutch depressed?

Does the clutch feel the same as it usually does, any pedal vibration etc?

I am not sure if the clutch has anything to do with it. When I first start the car the noise is there and then it goes away (as in the video) once the noise is gone it does sometimes kick back in again on it's own. It seems that when I press the clutch down it comes back. No vibrations through the clutch pedal and it feels normal.

I think it may be starter related as car was fine before fitting the hi torque motor. In the last video where the car is swicthed off you can hear a what sounds like a starter motor sound.

[Ribol]

MPoxon said:

I think it may be starter related as car was fine before fitting the hi torque motor. In the last video where the car is swicthed off you can hear a what sounds like a starter motor sound.

Ok.

In that case I would go with AJ, although the way the immobilser is wired up it cannot make a starter come on randomly if it messes about.
Assuming you have nothing connected to the starter other than your new 12V exciter interupted by a switch then it would suggest a faulty switch, shorting wiring or a starter issue.

I hope the 12V is not perm live because otherwise if the new switch is messing about or you have a short it could do it any time!

[MPoxon]

Ribol said:

Ok.

In that case I would go with AJ, although the way the immobilser is wired up it cannot make a starter come on randomly if it messes about.
Assuming you have nothing connected to the starter other than your new 12V exciter interupted by a switch then it would suggest a faulty switch, shorting wiring or a starter issue.

I hope the 12V is not perm live because otherwise if the new switch is messing about or you have a short it could do it any time!

I know the switch is OK as while the noise is happening I can operate the switch and the starter motor cranks the engine again and makes a different sound. The mechanical sound in the video sounds like the starter pinion is engaged but without the motor cranking if that is possible. Or of course something completely starter motor unrelated.

[Ribol]

Reading back through your post would it be fair to say the exact same problem was there before you changed the starter and is still the same with the new one (forget the current draw issues)?

[MPoxon]

Ribol said:

Reading back through your post would it be fair to say the exact same problem was there before you changed the starter and is still the same with the new one (forget the current draw issues)?

No different issue. The old starter motor would over crank when the engine was hot (eg when I stopped for fuel). This was exactly the same as if the key was permanently turned in the ignition even after the engine had started.

The new starter cranks the engine fine and does not overcrank as when the noise in the video happens I can operate the switch and the starter kicks back in over the top. I wonder if the pinion is not quite retracting far enough (if that is even possible) or whether the issue is something worse.

[Ribol]

I once had a car that did something similar, it turned out to be the spacer that stops the bendix from sliding too far towards the starter nose cone had broken and fallen off. This allowed the bendix to be kept in mesh with the ring gear (regardless of ign sw position) until it was revved when it would throw it out rather than destroy it.

But who knows, this is just pure guesswork, which could go horribly wrong - I certainly would not drive the car like this.

[MPoxon]

Thanks for your advice Ivan.

I am going to see if I can refit the old starter motor and see if the 'new' noise is still present. At least this way i can either prove the issue is the starter motor or eliminate it from the investigation. The video does not demonstrate the noise very well but it is very loud and high pitched.

Matthew

[Guillotine]

yep, take the starter out and have a look at the teeth and circlip.
Could be loose on the shaft, but pushed up against the flywheel when engaged.

Which starter is it?

A

[MPoxon]

Guillotine said:

yep, take the starter out and have a look at the teeth and circlip.
Could be loose on the shaft, but pushed up against the flywheel when engaged.

Which starter is it?

A

Cheers Andy I will have a look at that when I get the starter off again.

I will send you a PM with the source and make of the starter as I know some people can get a little excited sometimes.

[Aussie John]

Hi Matthew, what was the outcome?

[MPoxon]

Aussie John said:

Hi Matthew, what was the outcome?

It does not look too good to be honest.

I do not have anything conclusive but since I last posted I had a mechanic friend take a quick look at. His preliminary conclusion suggests that I may have overlooked the significance of the clutch in this. I automatically discounted this as has been working fine before and the only thing that has changed is the starter.

The mechanic suspects based on hearing the engine run and operating the clutch that there may be an issue with the clutch or clutch bearing that is causing the flywheel to move which could be why the starter is re-engaging. The mechanic also observed that the car smells of burnt clutch when idling in neutral. To further re-enforce this theory my small oil leak has now become quite a large oil leak in that you can see it dripping underneath the car. The oil appears to be dripping from the back of the engine.

The car is booked in next week at my preferred TVR specialist so I know more when a full inspection has been completed.

[Ribol]

MPoxon said:

The mechanic suspects based on hearing the engine run and operating the clutch that there may be an issue with the clutch or clutch bearing that is causing the flywheel to move which could be why the starter is re-engaging.

Whilst I would not dismiss the clutch being at fault, not so sure about the flywheel moving bit, that would be a very odd thing to go wrong

Good luck with it anyway, hopefuly it won't hurt(£) too much.

[Simon says]

Hope it's clutch related and not crank

[Ribol]

Simon says said:

Hope it's clutch related and not crank

Surely it wouldn't run like that when the noise is absent if the crank had gone?

[Jammy Dodger]

burning clutch is a pretty distinctive smell - i think you would have noticed it yourself..

[Ribol]

Jammy Dodger said:

burning clutch is a pretty distinctive smell - i think you would have noticed it yourself..

Oil getting blown on to the exhaust?