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Water Pump Leak...Again

Hi everyone!

I drive a 1998 Jeep Cherokee, 4L 6C. I’m about to replace my water pump gasket for the 3rd time. Every time I do it, the coolant starts leaking again after a few months. I think I’m using a quality gasket. I also use the gooey stuff on both sides of the gasket.

Any tips? Am I doing something wrong?

Is there a certain order in which I should be tightening the bolts on the water pump?

Could it be that I haven’t been cleaning the pump and the engine block enough?

The water pump itself is good. I purchased it new in 2015.

What gooey stuff? Clean both surfaces real good and put the gasket on dry.

Clean both surfaces.

Brake cleaner helps in doing this.

Then take this product, https://www.permatex.com/products/gasketing/gasket-sealants/permatex-high-tack-spray-a-gasket-sealant/ and apply to the side of the gasket that goes on the water pump.

This will hold the gasket in place while installing the water pump.

Tester

Could the leak be from the front manifold bolt which mounts into a hole open to the water jacket. Seeping leaks there are common.

On my Ford truck I’ve always done it the way @Tester describes above and never had a leak develop yet. (I don’t use the spray type, but I do use a permatex brand gasket sealant.) There’s a half dozen bolts located roughly in equal distances around the perimeter. I tighten them like I tighten the lug nuts on the wheel, in a criss-cross pattern, and in three rounds of torque. So if the final torque value spec is 30 foot pounds say, I’ll tighten them all to 10 foot pounds in a criss-cross pattern, then all to 20, then finally all to 30. You might try that technique, might help, couldn’t hurt. Make sure the bolts are installed in the spot they are supposed to go of course if they are of different lengths. On my truck’s water pump there’s quite an assortment of bolt lengths involved, so it is easy to get the wrong length bolt in the wrong place if I’m not careful. Doing that could cause a leak.

I’ve always used the sealer on both sides but don’t suppose it really makes much difference. I always coated the bolts with sealer too as anti seize but also would take care of any leakage as mentioned above. I think it is just good practice to also alternate the tightening of the bolts so the pump doesn’t warp. Frustrating though huh?

I’m not an expert on those mopar 4 liter straight 6 engines . . .

Do any of the water pump bolts happen to go through coolant passages? If so, you’ll need to coat the threads with an appropriate sealer