Engine Clattering noise and Oil leak C220

[RAV]

I have a hoping to get some opinions on the following problem on my father's C220 (1995).

There is a clattering noise from the front of the engine. I held a screwdriver to suspect component as suggested by a posting in this forum and it appears to be coming from the component shown it picture 1. It seems that this is a water pump but my mechanical knowledge is very limited. Whilst trying to locate this problem, I also noticed some leakage of possible oil?? behind the poly-v-belt as shown in picture 2. I am wandering (and hoping!) if these two symptoms are linked but it seems there is a fair distance between the two.

The car has done on 54,000 miles but there have been a multitude of problems since my father bought it 8 months back. These have included ECU repairs twice!

I would be grateful to receive any advice or suggestions. Does anyone know a good and affordable independent mechanic in the vicinity of Milton Keynes?

 

[marcos]

I had an M-Registration C220 and covered over 120,000 miles in it with virtually no problems, superb car and the most reliable car I have ever owned, drove better than new when I sold it.
I don't want to sound all doom and gloom but 54,000 miles in nearly 10 years is just silly, can you verify the mileage? May have been clocked and is now running into probs.

Sorry just remebered that as it hit 100k the water pump made funny noises and had to be changed so could be the same problem.
BTW the registration dosen't end OGS by any chance.

 

[RAV]

The MOTs and service stamps (Mercedes) seem to indicate consistency in the mileage. However the thought did also cross my mind. The registration does not end in OGS - why do you ask?

This car is early N plate but I doubt if it is mechanically different from yours.

 

[big x]

The waterpump is in fact shown in your second photo.The oil weep looks to be a leaking head gasket from the front left of the block,very common on Merc 4 cylinder engines.I've read that specialists like Georgr Fraser say the engine can soldier on for many miles in this condition (as long of course there is no oil leaking into the cooling system.Check the expansion tank for oil droplets.)
The noise may be the belt tensioner shown below your arrow.This along with the polybelt is best replaced when fitting a new waterpump.
Hopefully one of the guys who work on these cars can add more info.

adam

 

[marcos]

The MOTs and service stamps (Mercedes) seem to indicate consistency in the mileage. However the thought did also cross my mind. The registration does not end in OGS - why do you ask?

This car is early N plate but I doubt if it is mechanically different from yours.

The reason I asked about the reg No was because I got a phone call about my old car ages ago from a private buyer wanting me to verify the mileage when I sold it, it had been turned back to about 45k. The bloke found my number on one of my business cards that was wedged in the handbook.

 

[RAV]

The reason I asked about the reg No was because I got a phone call about my old car ages ago from a private buyer wanting me to verify the mileage when I sold it, it had been turned back to about 45k. The bloke found my number on one of my business cards that was wedged in the handbook.

The person who sold the car was the sole owner therefore I can only assume that the mileage is genuine - The ECU problem apppears to be common in some of these models as there was a specialist repair company advertising that they repair these units from these models. At present, I am not doubting the mileage but obviously you don't expect many non wear and tear issues at this mileage.

 

[andy_k]

in your first image you show the thermostat housing - that really can't be causing any noise at all, the second shot, as has already been said looks like the waterpump.

My guess is that the belt tensioner has failed as with everything mechanical they have a finite life and if somebody has over tensioned it at some point that will significantly shorten it's life.

It's a DIY job and shouldn't take too long but be prepared to lose a bit of skin off your knuckles and do quite a lot of swearing

I wouldn't stress on the oil seepage either but I would make sure I cleaned it up to work out just where it was coming from


Andy

 

[RAV]

Thanks for your useful comments. Just goes to prove my ignorance on the subject - about suspecting the thermostat to be the water pump. I was convinced of the clattering coming from the arrowed component in picture 1 - now identified as the thermostat. I guess the screwdriver to the ear is not conclusive! The clattering occurs at idle and certain other revs but at all revs.

Andy, Adam, can you tell me what the belt tensioner looks like? Is there a simple test to prove that the noise is attributable to this? Would this require adjusting or replacing? I suppose that at present the water pump is not suspected.

Again thanks for your help.

 

[Ian B Walker]

Rav dont know if this helps but this is the tensioner adjustment nut of a 201 / 124

 

[big x]

Rav..your photo no. 1 shows it, a black bodied piston behind the belt with printed on writing.There is no ajustment.
With the engine running try puting a long screwdriver behind it and see if it moves when pryed (Be careful with loose clothing etc.) If the noise changes
you have found the source.You may be able to reduce the noise by playing around with it.
Haynes make a manual covering the 4 cylinder c-class, well worth getting as
things like this are quite easy for the DIY person to fit.

adam

 

[RAV]

Rav..your photo no. 1 shows it, a black bodied piston behind the belt with printed on writing.There is no ajustment.
With the engine running try puting a long screwdriver behind it and see if it moves when pryed (Be careful with loose clothing etc.) If the noise changes
you have found the source.You may be able to reduce the noise by playing around with it.
Haynes make a manual covering the 4 cylinder c-class, well worth getting as
things like this are quite easy for the DIY person to fit.

adam

Thanks Adam - it seems that you were spot on. By wedging a screwdriver between the casing and the belt tensioner the noise did disappear for that moment (well, the main noise anyway). Would you still consider replacing the poly-v-belt at the same time or is this not necessary? Also, is it safe to keep driving the car with the tensioner in this condition?

I will get the Haynes manual to have a look - with my level of skill there is slim chance that I might attempt myself .

I will also cleanup the oil seepage and try to identify the source of this.

 

[andy_k]

I'd consider changing the poly belt, without the tensioner operating properly there's a possibility it's got a little frayed at the edges or stressed in some other way. although there is little risk of any serious damage should it fail it's an inconvenience that spending about £15 will easily avoid

Is it safe to drive the car with the tensioner in this condition?

hmmmm, I'd rather not answer that one for you. If it were my car, I would probably drive it until I bought and fitted the replacement part but I'm not suggesting that is either the correct thing to do or even sensible. If it's only just started to wear then it's unlikely to fail completely in the short term but in all honesty you are not going to get away without changing it so a.s.a.p. would be my best advice.

Andy

 

[RAV]

Okay, I got the Haynes manual but could not find anything explicit about changing the belt tensioner damper for the petrol version of the C220. So returned to the car and noticed the actual cause of the clattering was in fact some play in the damper fixing (top bolt in in picture 1).There was some side to side movement at the top fixing of the damper so even by hold it with the fingers, the noise disappeared. I optimistically reckoned that the bolt just needed tightening up but infact it was already tight. It just appears that the damper is slighlty loose in the rubber over the metal collar and therefore is free to move.

Unless anybody has other opinions, I am now of the opinion that the damper itself is functioning okay and the clattering noise is only a nuisance which may be resolved by some kind of improvisation.

Anyway, I was still curious about how to remove the damper completely. I could undo the top bolt but could not figure out how the bottom bolt was fixed behind the tensioning pulley.

I have also cleaned the oil up in order to monitor the seepage is from.

 

[BimMerc]

did you buy it off ebay?

 

[RAV]

did you buy it off ebay?

No, actually it was bought from someone I had known of and therefore I had and still have reasonable confidence of the history. This is my first experience of Mercs and although they are nice to drive, I have not had to open the bonnet so much on any other car I have owned. But the ECU problems were the main cause of this and it appears that the clattering is just some play rather than failure of a component. As for the oil leak... I taking the advice above that it is common!