Northstar water pump stuck

[Bob Steur]

Replacing the water pump on wife's 2000 Deville DTS, 180,000 miles, makes a noise and leaks coolant, no heat, pretty sure it's the water pump. Removed air cleaner, hoses, belt, etc to get to it. I have the special tool ( a huge impact socket that is supposed to be turned 20 degrees clockwise to remove.) I have used a 1/2 inch ratchet and even an electric impact gun on it to no avail, I can't get the darn thing off.

I don't want to break the aluminum housing, and it doesn't look like it will come off the car without a lot of work. Can the pump be taken apart to make removal easier? How much force can I apply? Should I spray PB Blaster on it?

Anyone done this job? Any advice or suggestions? Any help is appreciated, thanks!

Bob

[Bob Steur]

False alarm, folks, I got it out. I had bent some of the "tangs" forward, I guess I might have turned it too far. Bent them back, backed it out and it came out. Now to put the new water pump in and put it all together and fill it up. No damage to the aluminum housing. I've certainly seen water pumps that are harder to change- Northstar is a pretty nice design in this regard. 

[David King (kz78hy)]

I would put on new belts while your at it.  I have an Aurora w/the 4.0L northstar and lost the waterpump belt at 150k.  Thank goodness I was able to get it off the road and shut down before the engine got really hot.  It just started to touch the red area on the gauge.  So no problem from my lazy maintenance.  Those belts are not much fun to replace.

David

[TJ Hopland]

They made up for the easy to change water pump with the starter location.   

For those that dont know the water pump runs off one of the 4 overhead cams so its more or less on the top of the engine.   The starter is in the middle of the V which means under the intake manifold so there are just a few things that need to be removed to even see the thing. 

I still think those are neat motors.   My current fixation is on diesels but before I got into those I had dreamed up a few unique applications for Northstar swaps. 

[Roger Zimmermann]

I would also replace the thermostat. I had a leaking water pump on my 2000 DTS; the dealer replaced it and one or two weeks later I noticed that the temperature was too low.
I do work myself on my old cars, but not on "modern" ones. As long as a dealer can do it, I let him do...

Roger