94 W202 C280 Water Leak

[GB Classic]

Hi all

I have had a water leak on my 94 C280 for about 2 years now. It is hard to see where the actual water leak is coming from but it appears to be near to the front of the nearside engine block Possibly around the water pump area but it is just so difficult to see.

I had an independent garage take a look at it about 18 months ago and they could not tell either, and said that they would have to take the manifolds off just to get a better idea, but advised that this would be a lot of money just to get a diagnosis. They put some K-Seal in at the time and this stopped the leak for about a year but then it came back and needed about 2 litres of water a week.

I lived with it like this until recently the leak became worse. I added another dose of K-Seal in the hope that this would fix it again but this time it made no difference, and I now have to top up the coolant every couple of days. I still cant tell exactly where it is coming from but it could be the water pump gasket?

Any ideas - and if it is the water pump gasket is this a simple job to tackle?

Any feedback most appreciated.

 

[kth286]

It is very likely to be the water pump itself.

It is a big job on that engine (I think 6 hours is quoted by Merc) and needs to have an experienced person that has done it before ideally as there is a set of thin wobblies required for the inaccessible water pump nuts, and specialised knowledge re the dismantling and various pipe connections such as the one to engine oil cooler etc.

If you are into DIY make sure to get everything prepared before hand with all proper Merc instructions.

I did mine over a long weekend and took the oportunity to change hoses, thermostat, polybelt, new coolant etc etc whilst everything was dimantled.

Used all Merc original parts.

Never leaked since (3 years ago).

 

[GB Classic]

Hi there

Thanks very much for your detailed and informative reply - a mercedes time of 6 hours sounds a bit scary!

I was rather fearful that it could be the pump although I couldn't see any leakage from the spindle behind the pulley and had rather hoped that it may have been something else.

Although I used to be a mechaninc I don't feel its a job I could tackle these days (bad back and all that) so I will have to get a few few quotes and weigh up the options.

Thanks again for your post.

Best regards

 

[aziz]

is your car overheating or is it normal?
I am asking this because my 190e was doing the same thing and nobody could tell where the water was leaking from despite continuously topping it up.
I took it to Mercedes and they spent two hours diagnosing the issue. They could not find anything there.
One day I was working on the car when the bonnet was up, I noticed that the water was coming out of the overflow because the fan was not working.

 

[GB Classic]

Hi there

is your car overheating or is it normal?

No, the temperature is quite normal - ususally just around the 80 degree mark, but thanks for the suggestion. I have checked the overflow and the fans are all working properly.

Best regards