Hello, I have a little problem. I am in the middle of trying to change the water pump on my 83 chevy full size blazer, 6.2L diesel. I have removed all accompaning belt, fan, fan shroud, power sterring, etc. and all bolts from the water pump but cannot get the thing of the engine, feels like the thing is seized onto the block...... The new water pump looks like it has threaded or tapped holes for studs to go onto the block?.... is this the case? and can I fix it without a press puller?.......

Welcome to the forum!
The water pump is fastened to the back side of the timing cover. Yep, that whole cover has to come off, and bolts removed from the backside. But this will give you a chance to inspect the timing chain at the same time. I'm sure others will chime in with more detail shortly.

Yep..there are several bolts that go into the waterpump backwards from the back of a big steel plate that the water pump hangs on. Dumbest design I ever saw. Be sure and clean the plate thoroughly and use the blue RTV gasket maker to put the plate back on the block. Sometimes the plates have pits artound where the pump goes, which I think is caused by cavitation corrosion. If it is real bad, you might need a new plate.

Like was previously mentioned the entire cover has to come off. There are bolts with 15mm heads that go through the water pump casting, but there are also two hidden bolts with 13 mm heads on the bottom side of the water pump that thread into the timing cover along with all of the 13mm headed bolts on the upper part of the tin.

Thanks heap!! that really answered my question. I;ll let ya know when I get er done! :D

That's not a fun job all either. Make sure you use new gaskets on that thing, there are not only oil seals and the water pump seal to worry about, there are also water passages behind that cover that can leak coolant into the crankcase if they aren't sealed correctly.

I used gaskets on EVERYTHING, along with a bit of Blue. She is now running like a stripped ass ape once again.......

Thanks a heap everyone!!

good job, had you missed some bolts or just needed to giver a little?

Nah, I just couldn't get the dang cover of the darn crankshaft thing. Found out my truck is fithy as heck underneath..... :D

lol, most of em are...well maybe a quick power wash and look again...maybe theres a bolt burried in all that mollymud :P

So High Sierra, a gasket behind the water pump can leak coolant into the oil? Sounds like the problem that I have. I am losing coolant around the water pump area and getting some in my oil. I originally thought head gasket but exhaust is not blowing out the radiator and no oil in water. I am going to replace the water pump and the seals that you refer to and then change oil and see what happens. I am definately going to wash the engine first. Any places to stay away from?