I replaced my water pump with an ACDelco one a couple years ago at about 160k miles. It was starting to weep and I was getting a belt squeak on startup that I couldn't trace to anything else. Replaced the thermostat, radiator hoses, idler pulley, and belt tensioner at the same time because most of them were original to the truck too and I figured I might as well replace the cheap stuff as long as I was in there anyway to prevent future headaches. Belt squeak gone and running like champ ever since.

Fan clutch tool was dead simple: go to any name-brand auto parts store and "rent" one for free. Cost effective and dead simple, and works better than trying to wrestle with a crescent wrench or such anyway. Easily the best $0 I spent on that whole project.

Also why are we talking in a thread from 2009? How is this even allowed to happen? OP and all the previous participants have either fixed their problems or moved on other vehicles at this point, it's a poster child for necro-posting.

 

I’m on my original water pump at 205,000. Did replace the leaking radiator at around 105,000 though.

George

 

When I first got my Blazer it had only 42k miles and water pump was done.

I don't think age or miles has anything to do with a water pump.

Just luck.

LOL.

 

And perhaps how well the cooling system is maintained?

 

Of course,but didnt the Almighty GM push that Dexcool was good for 100k miles.

Yes, or 5 years,,,,,,,,,,,,, but how many people took the radiator cap off to see a beautiful bright coolaid orange color and decided, "I must change this coolant because its over 5 years old", even if the car has only 42k miles.

I would bet dollars to yen that even the main GM dealeship thought, "this vehicle has only 42k miles, coolant looks good, even if we change it, it wont look any different, Dexcool is good for 100k miles, forget it".

The reason for all the litigation regarding Dexcool?????????

 

My answer is no, it is not a maintenance item. Do it when it starts leaking or when the engine FIRST starts overheating. I just did this job with the help of the good old Youtube and esp.the Huber Ranch posts which were very detailed. I think he left off putting high temp water pump sealant on the four 14 mm bolts that hold on the water pump to the block. I got a pair of thin, flimsy gaskets with my NAPA new water pump. So I bought a pair of heavy duty Fel-Pro gaskets for $4.59. They were sturdier looking that the ones provided. I would also recommend buying a new vs a re manufactured water pump. I feel the first choice would be AC Delco. I bought a new NAPA water pump for only $60.00. I also recommend replacing the GM style pinch clamp with a screw on hose clamp for the lower radiator hose. This was suggested by Mr. Huber of Huber Ranch vid's. Failing water pumps seem to be a problem with 4.3 L V6 and the V8's and GM in general. Some think this is due to poor design, I think it may be due to Dex -Cool sludging up.and causing failure. My only concern with the NAPA water pump was a ridge or edge on the two large water openings due to machining. This was easily removed with a hone or a sanding disc.