C124 Front End Noises

[Ade B]

After a long term intermittent chirrup from what seems to be the steering pump area, over the last week and after a 300 mile round trip on Friday the noise has become loud enough that I can hear it from inside whilst driving through traffic.

Basically a loud and continuous dry metallic cricket like chirruping from the front (steering pump side) - not fan belt squeal.

Took it to a local non MB specialist back street place this morning as I'm afraid to drive any distance for fear of failure of a major bit (water pump, PAS pump, idler pulley etc.) leaving me stranded.. of course the car decided to be defiantly quiet and the chap was unable to draw any conclusions based on an initial visual inspection but has asked me to bring it back thursday so he can put a new belt on it and have a poke about.

This hasn't filled me with confidence.

I had a new serpentine belt and tensioner 3 years/ 38K miles ago.. what's their usual life expectancy - based on my brief inspection the belt looks ok.

What should I ask him to check and in what order?

TIA

Ade

 

[Dave Lewis]

Just had a similar problem with mine - it turned out to be the bearing on the fan pulley. This was an expensive part, as it includes a cast bracket - only available from MB at £167-90 inc VAT . Very difficult to trace the noise, even with a stethoscope. We found it by a process of elimination, substituting the various pulleys from another engine. Check the water pump though.

 

[bolide]

Engine off, give each of the pulleys a wiggle in turn. If you find one with a bit of play you may have your suspect

Engine on, you can try spraying WD40 (via a tube) on the bearings of each pulley in turn. If one quietens down then again you may have your suspect

Nick Froome

 

[Ade B]

Update:

Car in Thursday, cam sensor (?) broken Thursday pm, part arrived Thursday pm, new serpentine belt ordered..

Wrong belt turns up Friday am, correct belt turns up Friday pm - car not ready end of Friday.

Call this morning and leave message... travel across London on bus with dog and family to see friends, call from garage that belt is back on, car is fine and can be picked up before 2 - I'm in the wrong bit of the city...

All pulleys checked, noise gone apparently. Bill for £180 inc. VAT..

I pick the car up Monday.


Ade

wishing he'd risked the drive to Portsmouth...

 

[Ade B]

Engine off, give each of the pulleys a wiggle in turn. If you find one with a bit of play you may have your suspect

Engine on, you can try spraying WD40 (via a tube) on the bearings of each pulley in turn. If one quietens down then again you may have your suspect

Nick Froome

Well the noise has returned some 4 months after the last trip to the garage and whilst I can keep it out by keeping windows and sunroof closed, its obviously not a long term solution

Poking about with an engine stethescope doesn't reveal any grindy noises and using Nick's method above, all pulleys I can reach appear solid (I guess to check properly you need to remove the belt) With engine on and squirting WD40 about, the culprit appears to be the AC compressor.

My A124 owning neighbour reckons some spray grease might sort out the noise in the interim..

This is an aftermarket Davia (I think) number. Any idea if its possible to repair/replace bearings on these.

Thanks

Ade

 

[Ade B]

Car is currently in garage - they reckon its a belt noise only and can't find anything wrong with the pulleys... which is a relief.

Found this a useful link, I'm guessing something is out of alignment somewhere as the last belt went on at Christmas...


Ade

 

[kth286]

Just had a similar problem with mine - it turned out to be the bearing on the fan pulley. This was an expensive part, as it includes a cast bracket - only available from MB at £167-90 inc VAT . Very difficult to trace the noise, even with a stethoscope. We found it by a process of elimination, substituting the various pulleys from another engine. Check the water pump though.

Dave

Do you have the old bracket by any chance ?

 

[Dave Lewis]

Dave

Do you have the old bracket by any chance ?

I'm afraid not, it got binned. The bearing/pulley wasn't available separately, so I didn't think it was worth keeping.