Tips and Tricks for replacing water pump?

[6.2Blazer]

My water pump is toast and I will be replacing it tomorrow. After a quick look it seems to be about the same setup as a gas engine, except for maybe having to remove some more brackets (lower alternator and lower p/s???).

Any tips or tricks anybody can offer with experience in doing this.

 

[arveetek]

Actually it's quite different from the small block gassers. I never did like the design of the water pump on the 6.2L.

Anyway, you will have to remove the whole front cover of the engine. There are the usual bolts going into the front of the water pump into the block, but then there are several smaller bolts going in from the backside of the front cover into the water pump. In other words, you have to remove all the bolts holding the water pump and front cover on, remove the front cover/water pump assembly, and then unbolt the water pump from the front cover.

You will have to remove all accessory brackets, remove the oil intake tube, and all the small and large bolts. The small bolts are along the top of the front cover in front of the injection pump housing. The large ones go through the water pump, through the front cover, and into the block. There are also a couple of smaller diameter, longer bolts that are on the bottom side of the pump. They're hard to see, but you can feel them. They're easy to miss.

Make a template out of a piece of cardboard with holes punched in it to keep track of all the bolts. They vary in length and purpose. Some are studs with nuts on the end to help support accessory brackets. Some are just plain bolts. The diameters of the bolts vary as well. You don't want to get them mixed up.

Make sure you use a thread sealer on all the bolts that go through the water jacket when you install the new pump.

All in all it's not too difficult, just time consuming because of the way GM designed the thing.

Casey

 

[6.2Blazer]

Hmmm, sounds like it will take at least a couple of hours.

I know the new pump comes with a gasket, but I'm assuming you need to re-seal the front cover....what should I use?

 

[imiceman44]

[ QUOTE ]
Hmmm, sounds like it will take at least a couple of hours.

I know the new pump comes with a gasket, but I'm assuming you need to re-seal the front cover....what should I use?

[/ QUOTE ]

If you ar etalking about the paper he mentionned it was to keep the bolts from getting mixed up.
I prefer using a gasket as opposed to silicone for the correct spacing and clean look, but some people use the silicone with success so you have your choice.
I would try the parts store first they might have the gasket for under $5.

 

[arveetek]

Yes, you need to reseal the front cover. I usually use high-temp silicone.

Casey

 

[6.2Blazer]

Took me about 3 hours with a leisurely pace. I was a little P.O.ed that I had to remove the fitting from the crossover pipe to get the last front cover bolt off....what was GM thinking.

 

[tRustyK5]

Blame Detroit diesel...it was their design. /forums/images/graemlins/dunno.gif

Rene

 

[6.2Blazer]

I'm sure GM had some say in the overall design and packaging.

 

[arveetek]

Oh yeah! I forgot about the bypass hose fitting in the water crossover pipe! It makes ya nervous, doesn't it, trying to remove a tight fitting that's been in that aluminum for who knows how many years? /forums/images/graemlins/eek.gif

Glad to hear ya got it done all right. /forums/images/graemlins/thumb.gif

Casey

 

[6.2Blazer]

Tell me about it! I took the fitting off of the old water pump first so there would be room to put a deep well 6-point socket and a breaker bar on it. Tried a wrench at first but it started to round off and I couldn't get very good leverage on it.

 

[78GMC1/2TON4x4]

Might as well put in a new thermostat...under 10 bucks i think. I put a new water pump on my 6.2 4 months ago or so and boy was it fun! Its such a mess with the brackets and crap. Make sure you keep track of where the bolts, nuts, and studs go. Have Fun! /forums/images/graemlins/histerical.gif /forums/images/graemlins/truck.gif