Water Pump Replacement

[molehole]

Hi Everyone
I am getting ready in the next few days to replace the water pump on my 96 Blazer. It is obviously leaking antifreeze so it time for it to go. I have done water pump replacements on my 71 monte carlo and my dads 87 silverado and they were pretty simple and straight forward. I was wondering if there is anything I need to know before I dive in to this one. Obviously I need to drain the coolant and remove the belt but what else do I need to do? Thanks guys, Mike

[blazee]

It's not that bad of a job.

1)Drain the coolant:

2)Remove the shroud:
7-10 mm bolts

3)Remove the fan and clutch:
There is no need to separate the fan from the clutch. The whole thing threads on to the end of the water pump. I don't know the size, because rather than break out all my wrenches, I just grabbed an 18 inch crescent wrench. Place the wrench on the nut and tap loose with a hammer. the tapping will break it loose. You have to tap it, if you just try to loosen it, the belt won't hold it and the whole thing will turn. After it breaks loose just spin it off.

4)Break loose the bolts holding the pulley on:
4- 13 mm or 1/2" bolts
Just break them loose, don't remove them

5) Remove the serpentine belt

6) Remove the pulley:
Finish removing the bolts holding the pulley and remove the pulley

7) Disconnect the hoses

8) Remove the old pump:
4-14 mm or 9/16" bolts

9) Clean the surface:
Remove all traces of the old gasket.

10) Install new pump:
Apply a bead of blue Permatex around the holes on both sides of the gaskets, put them on the pump and insert the bolts through the holes to hold the gaskets in place. Carefully lower the pump in to position. Thread the bolts into the block and snug them. Then remove the bolts one at a time, add the permatex to the threads, and then reinsert. (only do one at a time so that the pump doesn't shift and disturb the mating surfaces) Then tighten all the bolts.

11) Reinstall everything in reverse.

There will be a lot of air trapped in the system, so after you fill it, get the engine to operating temperature, shut it off, let it cool, then add more. The air trapped in the system can cause your engine to over heat if left unattended.
I suggest filling the system with water only and run it like that for a day or two just to make sure there are no leaks. That way you don't waste your antifreeze if you have to do further repairs.

[JA no Y]

If you have changed a water pump before you shouldn't have any trouble with the one on your blazer. I changed the one on my girlfriends blazer in her driveway with a flashlight (she just couldn't wait till the morning). Just make sure you loosen the nuts on the clutch fan before you take the belt off. The belt will help keep the fan from turning when you go to loosen the nuts. Same could be said for tightening them too.

[molehole]

Everything went fine with the replacement. Thanks for the directions Blazee. Ah no more puking antifreeze. Thanks again guys.

[Absolut Talent]

Thanks for the great instructions Blazee.

I had to replace my waterpump, but I had to decide to do it on a hot chicago sunday

And that tip about just removing the fan with the clutch...excellent. I had to buy a new wrench (my 10" didnt open wide enough), but it was a lot easier to remove one part then 4 little bolts.



After I got my new pump installed, let it warm up and I noticed another leak. This time it was from one of the little hoses on the top (the left one). Figured I just didnt clamp it down good enough. So I let it cool, slid it down a little bit more, and now everythings great. Nextweek I will drain the system, do a flush+cleaner, then refill with good ol' dex. Then I can move on to my next batch of problems

[blazee]

You're welcome, guys. I'm glad that they helped.