bbirdwell

Looking for some opinions on possible replacement of water pump as preventive maintenance...

First, I firmly believe in replacing a part before it breaks and doing so on my own schedule. Simultaneously, I do not want to prematurely replace a part that has significant life remaining.

Upcoming maintenance in a couple of months at 150,000 miles. Items I have scheduled:
-Fuel filter and pumps. Will have 60K on this set so it will be time to replace. ~$950
-Tensioners, pulleys, belts. ~$460
-Oil and filter. ~$35 (edit: per hayseed's comment below, this is incorrect. more like $55 to $60)
-Replace alternator voltage regulator. Alternator on car is labeled "Rebuilt Bosch". Not indicated in the service records I have but replacement occurred prior to 44K miles on the car (that was the point where the car was repossessed from the original owner and ended up in the hands of the USAF F-16 pilot from whom I purchased the car). I would postulate the original alternator was the subject of a factory tech bulletin but I do not have confirmation. In any case, I figure on replacing the regulator so I won't have to worry about worn brushes. ~$35
--Now, on the requested input. Since I will have everything off of the front of the engine, now would be a good time to pre-emptively replace the water pump and 13-year-old coolant hoses. I don't want to perform all of the above work only to have the water pump later fail two hundred miles from home and have to get the car towed and then go back into the engine compartment (or pay dealership rates for them to perform the work). Next major maintenance for belts/pulleys/tensioners is 210,000 miles (yeah, I plan on keeping the car that long). Based on my limited experience with Mercedes (only a little over four years), I'm seeking input on the odds of the water pump failing between now and 210K miles. I come from decades in the Miata world and there one replaces the water pump every 120,000 miles or else. So, previous experience with non-Mercedes has me wary of potential and unknown (to me) failures of the M113 water pump. If replaced, I estimate ~$300 to $500.

Thoughts, recommendations, gratuitous insults/slurs about replacing the water pump now versus waiting it out to 210,000 miles?

hayseed

iTrader: (2)

just my .02 ,, if you have all that stuff off its not much more to take off the water pump and not that much additional cost ,,, hoses probably need it anyway. not sure I would replace the fuel pumps again/yet but that is your prerogative, I would consider replacing just the bearings in the steel tensioners and pullies if you can get actual nachi replacements. the plastic ones will break at some point … not sure how you replace oil/filter for $35 though -- 9 qts at 5 each

tw2

Yep if you are in there might as well. Hoses should be ok but I don't know how expensive they are. Certainly worth a thorough inspection.

He wrote the DIY for replacing the pulley bearings...