I'm on my 5th Water pump!
 

Just bought (2 months ago) a 1991 190E 2.6 -- the car was very well maintained.

In going through the service records, I find that it is now on its 5th water pump. The car only has 123,000 miles!

What is up with that? Otherwise, no major problems of any sort.

brookspw

Has the same person replaced rthe pump each time.if so They could have tightened the belt way to much,putting stress on the pump.just one thought.

Were they Mercedes OEM pumps or aftermarket?
Second - check that the belts on the water pump are not overtightened which could put undue pressure on the front pump bearing and cause premature failure. Adjust all belts to proper tension. That is only thing that I can think of.

Check all pulley ALIGNMENTS as well.

All were MB pumps. All but the 3rd one were replaced at the original dealership.

Next time in, I'll have them check the belts and pulleys.

Thanks -- brookspw

That's LOTS! MY Dad's 90 190E 2.6 is close to 200,000 miles, and it's on it's original water-pump.

If they are MB pumps, it soulds like an install problem, or other related problem is causing the new pumps to fail.

One thing (among many) to suspect is the viscofan operation. My manual states, "Temperature-controlled viscous fan couplings must be transported upright. Fot brief periods e.g. for installation purposes, the couping may be placed on the flange side, but never on the front side".

It also states, "The bimetal strip must not be bent or damaged".

I take this to mean they may no longer function properly.

My question would be, if one of the above occured during the first pump replacement, could that lead to a mistaken belief that the pump failed?

Just a thought.

Harry
86 300 SDL

MB replacement pumps are REMAN's & they do fail often!
I have had better luck with aftermarket "new" pumps. ie; Graf