Engine bearings or possibly just a bad pulley?

[jd24689]

Recently my c220d has developed a rattle/grind coming from the auxillary belt area, from 8 seconds in:

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Any thoughts if this could just be a bad pulley bearing? There is some play and noise from one the idler pulleys when spinning by hand (video below), could be the cuase?

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Is it ok to run the engine for a few seconds with the auxillary belt removed to see if the noise is still there?

Thanks in advance

 

[m80]

Aux belt off just means you lose power steering, alternator charging, coolant pump and AC.
It'll be ok to run if for a short while like that.

 

[jd24689]

Same noise with belt off.. anything else this could be or is it looking like engine bearing issue?

 

[m80]

Cam shaft, perhaps.
From worn cams and rattling followers??

 

[jd24689]

Any advice on next steps to get an exact diagnosis? Is it worth pulling the head to see what the cams and followers are looking like?

 

[m80]

Tbh I'm not sure I'm hearing what seems to have you concerned.

It's a 646 diesel (or possibly earlier version), they aren't quiet engines.
In these days of pushing us toward silly priced Duracell bunnies I can appreciate that this car might have great purpose to you, but it's a 203 so possibly not worth great effort or expense.

Issues such as exhaust leaks and air intake leaks can produce sounds that confuse.

I find it difficult to pin point individual noises under the bonnet of a diesel. Rather than trying to find what it is that concerns you it 'may' be easier to try using some good sound insulating mat and covering up areas to try and eliminate it. then you might have a better idea of the source, even if not an exact pin point.

Be careful to keep it and you clear of those rotating bits that'll pull stuff in though.

Camshaft is in the head, but accessible below the rocker cover.
The gaskets are often heavy rubber, and may be reusable.
Likely you would need to remove the fuel lines and other components.

How far you want to go with this is a reasonable consideration.

 

[jd24689]

Tbh I'm not sure I'm hearing what seems to have you concerned.

It's a 646 diesel (or possibly earlier version), they aren't quiet engines.
In these days of pushing us toward silly priced Duracell bunnies I can appreciate that this car might have great purpose to you, but it's a 203 so possibly not worth great effort or expense.

Issues such as exhaust leaks and air intake leaks can produce sounds that confuse.

I find it difficult to pin point individual noises under the bonnet of a diesel. Rather than trying to find what it is that concerns you it 'may' be easier to try using some good sound insulating mat and covering up areas to try and eliminate it. then you might have a better idea of the source, even if not an exact pin point.

Be careful to keep it and you clear of those rotating bits that'll pull stuff in though.

Camshaft is in the head, but accessible below the rocker cover.
The gaskets are often heavy rubber, and may be reusable.
Likely you would need to remove the fuel lines and other components.

How far you want to go with this is a reasonable consideration.

Thanks for the reply. I have uploaded another video where the noise can be heard a bit more clearly:

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It can be heard when the engine is revved just after the gas pedal is released and lingers for a bit, a rattle / bearing grind type noise.

Any ideas?

I could get the car on some ramps tomorrow and have a listen from underneath to try help pinpoint it.

 

[optimusprime]

No video showing for me ,,,dont know why .

 

[ALFAitalia]

None of them work for me.

 

[jd24689]

The videos should all be working now