Noise at cold start

[Crixus]

Hello!

I have this noise at cold start. Shorter noise at warm start. Does anyone recognize the noise below and what it could be related to?

https://youtu.be/aX1jngcvKN0

[Sahodgson]

Probably dirt or rust on the bendix stopping the pinion returning home fully and it’s catching on the flywheel.... remove starter motor, clean mechanism thoroughly and lightly oil, should be ok. Hopefully the picture makes some sense of this. On the Volvo starter motor the mechanism is covered by a shroud but can still be accessed. Had it on an Audi a few years ago.

[ampy]

Sahodgson's suggestion is worth following up on. Depending on what year your car is, it may not have a "bendix" but a solenoid that energises when you turn the key to "crank" and throws a gear forward to engage with the the flywheel ring gear which then turns the engine over. When you release the key the solenoid should power off and the gear should retract back away from the teeth of the ring gear. If it is sticking, you will get that sort of noise because the starter gears teeth will rub on the flywheel ring gear teeth. This will create vibration which helps the sticky gear eventually retract.

[Thommykent]

All automotive staters have a Bendix and a Solenoid, Study harder. Like Sahodgson says the Bendix can get dirty not fully retract.
http://www.autoelectro.co.uk/how-it-...starter-motors

[Tannaton]

Originally Posted by Thommykent

All automotive staters have a Bendix and a Solenoid, Study harder. Like Sahodgson says the Bendix can get dirty not fully retract.
http://www.autoelectro.co.uk/how-it-...starter-motors

No they don’t.

The term Bendix refers to the helical thread that the drive cog would be threaded on to, the sudden inertia of the motor starting would wind the cog along the shaft and hence engage it with the flywheel teeth.

99.9% of starter motors on modern cars do not have a Bendix mechanism, instead they have a pre-engagement solenoid (which also operates the electrical contacts).

Whilst this can suffer the same problems - ie become contaminated and be slow to or not retract - it’s not as common in the old days but it’s still a good place to start.

Just a note to the good - I see you’re a junior member - this forum is about helping people with their cars, not scoring points off each other.

[37 RUBY]

Terminology correctness aside, I find a mechanics stethoscope to be the most helpful when tracing noises.

https://www.clarketools.net/clarke-c...yABEgIDOPD_BwE

With a myriad of components that can or could groan upon starting it may help in identifying the culprit.

Starter motor on a manual transmission car is subject to clutch dust clogging said Bendix and its bearing. Less of a problem I surmise on a automatic transmission car but no doubt the age/mileage of components will play a part.

There is also the alternator pulley clutch which is known to make noise when failing.

On my own vehicle the headlight self-levelling servo is somewhat noisy.

I've listened to the YouTube clip and it could well be the starter pinion gear not returning to rest but equally it could be a dry bearing that squeals when first run.

....so it's a two person job, one using a listening device as suggested and t'other starting it up.

Good luck & please do let us know what you found.

[Thommykent]

Originally Posted by Tannaton

No they don’t.

The term Bendix refers to the helical thread that the drive cog would be threaded on to, the sudden inertia of the motor starting would wind the cog along the shaft and hence engage it with the flywheel teeth.

99.9% of starter motors on modern cars do not have a Bendix mechanism, instead they have a pre-engagement solenoid (which also operates the electrical contacts).

Whilst this can suffer the same problems - ie become contaminated and be slow to or not retract - it’s not as common in the old days but it’s still a good place to start.

Just a note to the good - I see you’re a junior member - this forum is about helping people with their cars, not scoring points off each other.

There is still a Bendix (ie Helical Thread )in an Inertial starter as you can see for a second time. Pre-engaged starters as you are referring to also have helical thread ( Bendix ). So no point scoring, only being correct. Just a note, pointing out being a premier over a junior is dosh.
https://www.howacarworks.com/basics/...g-system-works

[Tannaton]

Originally Posted by Thommykent

There is still a Bendix (ie Helical Thread )in an Inertial starter as you can see for a second time. Pre-engaged starters as you are referring to also have helical thread ( Bendix ). So no point scoring, only being correct. Just a note, pointing out being a premier over a junior is dosh.
https://www.howacarworks.com/basics/...g-system-works

Yep there is a bendix mechanism in an inertia starter, that's what engages the pinion to the flywheel. However inertia starters went out of fashion 40 years ago or so in favor of pre-engaged starters.

Whilst there is a similar thread on a pre-engaged starter, it's not a bendix mechanism, it's there to ensure that the pinion rotates a few degrees to ensure that it moves into mesh with the flywheel gear. It does not affect the advancement or retraction of the pinion. And it isn't going to be related to the OP's problem... as explained here:

https://www.youtube.com/watch?v=Sf6LqYBLljs

And I made no comment on my own membership...

[Thommykent]

Originally Posted by Tannaton

Yep there is a bendix mechanism in an inertia starter, that's what engages the pinion to the flywheel. However inertia starters went out of fashion 40 years ago or so in favor of pre-engaged starters.

Whilst there is a similar thread on a pre-engaged starter, it's not a bendix mechanism, it's there to ensure that the pinion rotates a few degrees to ensure that it moves into mesh with the flywheel gear. It does not affect the advancement or retraction of the pinion. And it isn't going to be related to the OP's problem... as explained here:

https://www.youtube.com/watch?v=Sf6LqYBLljs

And I made no comment on my own membership...

Membership status was implied in your comment. Your video shows a Bendix/ Helical drive and if it were to get dirty or worn it will not allow the gear to retract from the flywheel thus making a noise. It will cause the OP`s problem

[ampy]

Originally Posted by Tannaton

Yep there is a bendix mechanism in an inertia starter, that's what engages the pinion to the flywheel. However inertia starters went out of fashion 40 years ago or so in favor of pre-engaged starters.

Whilst there is a similar thread on a pre-engaged starter, it's not a bendix mechanism, it's there to ensure that the pinion rotates a few degrees to ensure that it moves into mesh with the flywheel gear. It does not affect the advancement or retraction of the pinion. And it isn't going to be related to the OP's problem... as explained here:

https://www.youtube.com/watch?v=Sf6LqYBLljs

And I made no comment on my own membership...

That is a great video. :-) They also use the proper terminology for the parts.
I think maybe the picture that Thommykent posted use the term Bendix alongside the term "Pinion" on the diagram to help older people identify with it. As you scroll down the page they go on to discuss it further. They only use the term "pinion" in the explanation of the parts and how they work.
Thanks,
Ampy.