Continuing problems with water pump

dallasdig

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I've replaced my water pump and it's still leaking. So I started over again cleaning it, adding new gasket and it still leaks. Both times it was fine for about 5 minutes but after 5 minutes would start leaking. Am I missing something? Could it be a problem with the part (Mopar from Mopar Parts Giant?) Is it leaking from somewhere other than the water pump?
 

Gollywomper

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Make sure you prep the block and pump perfectly. No gasket remaining at all. Like new condition. Install new gasket dry. Torque evenly to spec.
 
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Irun

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Did you replace the thermostat housing or clean and re-use the stock one? And, what water pump gasket did you use?
 

JMT

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Sometimes it’s very difficult see where the leak is coming from. Thermostat or water pump? Or both? The housing of the new water pump may not be flush with the block. Is it a Mopar or Chrysler pump? Those are the only two I’d use.
 

Jerry Bransford

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Even a very small shard of the old gasket remaining behind on a gasket seating surface can cause a leak. I use a fine steel brush to go over both gasket seating surfaces to insure they are pristine, with a light shining on them so I can see them well enough to know they are "surgically" clean before installing the new gasket and bolting things down.
 
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JSpike

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Do you have a coolant system pressure tester ? If you don't you need one, they are not that expensive, a good one is but you can get Chinese one relatively cheap.
Hook it up , warm up engine ,shut off and bring pressure up. With a good light and inspection mirror see where it's leaking. You should be able to pinpoint leak this way. Without pinpointing leak you could be peeing in wind😁
 
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dallasdig

dallasdig

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Thanks everyone. Yes it's a Mopar part and I'm confident I am getting all of the old gasket off and getting a good seal. I replaced the thermostat at the same time so I will double check and see if it's leaking from there.
 

hear

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I've never had to use any sort of RTV on a water pump/thermostat replacement. But also know that the torque spec is much lower than you might expect. 18 ft-lbs iirc, but don't take my word for it. One thing that can easily happen is that the t-stat can sort of fall out of the housing as you're moving it into place. In my experience it will leak like crazy if this happens. And on a related note, this soaked my gasket, but I had no issue re-using the otherwise new gasket. Somebody up above said install the gasket dry, but I believe they we referring to not using RTV.

And as a counterpoint to what others have stated, I've done several that weren't perfectly clean as described and have not had leaks. Which isn't to say they're wrong; I would still absolutely get it as clean as freaking possible. Good prep is the key on virtually everything in life. But if you can't get it perfect you may not need to have the mounting surface machined. I guess you only really know if you don't have it perfect and it leaks having controlled for all other variables.
 

Zorba

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As far as T-stat housings go, mine had a coplanarity issue, which is apparently fairly common. I ended up slathering yet another new gasket with Permatex #2, end of problem. The water pump had no such issues.