05-28-13, 11:18 AM
Just want to make a suggestion for anyone who needs to replace a water pump on a Northstar, or may eventually do so.I bought the Lisle water pump socket that most auto part retailers sell to remove the pump, and it proved useless for me. I couldn't keep it from slipping off the edge of the pump tangs. The correct tool has a hold down bracket that bolts on over the socket with two of the water pump cover bolts. That holds the socket down so that it can't slip off of the pump when you try to apply torque to it. I struggled with the Lisle socket for a half hour and gave up. Got the correct tool and it was a snap. Like they say- it's easy when you have the right tool for the job.
The correct GM tool is a Kent Moore j38816-1a. Hold down bracket is j38816-5. Pretty
expensive, but I found one used on ebay, or maybe you can borrow one. With the Lisle one you could probably make a bracket if you're willing to spend the time. I don't understand why Lisle doesn't provide a bracket. It seems pretty necessary to me. The FSM clearly shows it for removal and installation of the new pump.
I think the bracket was an after thought. Some come off easy and some fight you to the end.
Lisle tools are cheap. That's probably why they do not come with the bracket. They are also stamped steel (sheet metal) vs a HD machined part like the Kent Moore, Snap-On, KD (or mine) etc.
I made one years ago and have yet to use it (good insurance). I never did make the hold down bracket though. Any chance you could post or PM me some dimensions? Over all length & height, distance between mounting hole centers.
05-28-13, 05:14 PM
Here you go - probably a piece of 1/32" mild steel strap would do it. GM tool J38816-A/38816-5 strap
Measurements ........... an old pump cover and wing it ??
I know what it looks like, but I need dimensions. Depth and distance between bolt holes will be critical.
05-29-13, 05:39 PM
Perhaps we can get a member that has one to post the dimensions. Should be easy enough to fab up. The next one I do I will try and fab one up, definitely would have helped.
Yeah, after making the socket, the hold down will be a piece of cake.
06-02-13, 07:08 AM
The Lisle one broke on me when the one on my '99 fought till the end. It worked great on my '00. Autozone had it for their loan-a-tool and it looked durable enough I ended up buying a new one from them. Spent hours to remove the stuck pump.
06-15-13, 11:16 PM
I have a Matco brand water pump socket. Same as the lisle. It has a lifetime warranty (not sure about the lisle). I got sick of walking across the shop to the tool room every time I needed the tool so I bought the matco. Pretty cheaply built tool, but it works great. Ive warrantied it 2 times now, get about 100 pumps out of it before its junk. The secret to using these (and even the factory kent more tool) is to stick a 1/2 impact on them. Just make sure you do quick taps on the trigger, don't hold the trigger down. Even the really stuck water pumps come right out. When going back in with it also use quick taps on the trigger. Stop often and check to see if the stop tabs are against the stops. The hold down bracket also works, but after a co worker showed me the impact trick that's all I use now.
I think I paid $27 for the tool
Ofnaman, i am going to buy an impact drive to do this job after you posting your success with it. Could you please tell me what your tool's maximum torque is? I see several tools I can buy, whether pneumatic or electric, that go to 230-250 ft-lbs of torque. Would that be enough? Or do I have to pony up for the professional tool that goes to 500 ft-lbs? Also, I already tried to manually remove using just the socket and no backing plate, and of course had slippage and couldn't get it free. Now I have worn down (grooved) the tabs a bit with the socket tangs, so the socket is slipping off quicker now when I apply torque. Do you think this is going to be a problem when trying the impact tool? Do I just need to buy the backing plate now that the tabs are a little worn? Will even the backing plate solve the problem with the worn tabs, or do I have to try something completely different? Thanks for anyone's input.
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Are you trying to remove the water pump by turning it 1/5 turn clockwise (proper direction) ?
Get the highest torque rated impact you can. 250 is on the low side.
The hold down strap is very handy and maybe a must with worn tabs.