Solution to my leaking water pump weep hole?

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cruiser

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Greetings, all. The brand new water pump in my rebuilt slant six motor in my 1974 Duster has begun to leak slightly from the weep hole. This hole, as you know, is right under the fan shaft as it exits the pump housing. It's leaking enough to accumulate coolant on the floor of my garage. It's a real pain to change out the pump with all the hose connections, so I'm wondering the following: What if I just put some kind of plug in this hole? Would this stop the leak, or would the leak just migrate somewhere else? What if I just put some type of epoxy or silicone in the hole to keep it from leaking? Of course, I'd keep the goop away from the shaft inside. I really don't want to disassemble the front end of my engine again over such a small thing. Anybody got a great idea short of changing out the pump? Thanks - cruiser
 
When the anti-freeze is dripping out the weep hole, it means the shaft seal on the water pump is leaking.

Old water pump, NOS water pump, Brand New water pump, they all can weep out the weep hole when the shaft seal is no longer sealing.


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I believe the weep hole is there to protect the front shaft bearing being contaminated with coolant that has leaked past the seal, and now has the rear bearing awash.
 
Greetings, all. The brand new water pump in my rebuilt slant six motor in my 1974 Duster has begun to leak slightly from the weep hole. This hole, as you know, is right under the fan shaft as it exits the pump housing. It's leaking enough to accumulate coolant on the floor of my garage. It's a real pain to change out the pump with all the hose connections, so I'm wondering the following: What if I just put some kind of plug in this hole? Would this stop the leak, or would the leak just migrate somewhere else? What if I just put some type of epoxy or silicone in the hole to keep it from leaking? Of course, I'd keep the goop away from the shaft inside. I really don't want to disassemble the front end of my engine again over such a small thing. Anybody got a great idea short of changing out the pump? Thanks - cruiser
Replace the pump
 
Water pumps are actually designed knowing you can get a smidgen of coolant past the seal. The cavity ahead of the weep hole is intended to be large enough such that the coolant dries up before it ever comes out of the weep hole. If you've got coolant coming out and even enough to go onto the floor, that seal is leaking way more than intended. Bad deal but a replacement looks like is in your future...
 
I replaced the water pump on my 2006 Dodge Grand Caravan because it had signs of weeping from the weep hole.

Only later I saw in the FSM that some seepage there is "normal". Not to me it's not!
 
I believe the weep hole is there to protect the front shaft bearing being contaminated with coolant that has leaked past the seal, and now has the rear bearing awash.

Yes just use some sealer on it, it will be just fine.
NO, JUST NO!!!
The weep hole is an early warning system to let you know that the pump is going to fail so you don't get stranded. As said by SOOOO many above... REPLACE THE PUMP, ITS DAYS ARE NUMBERED!!!
 
The weep hole is there to prevent leaking coolant getting into the bearing. An occasional drip is ok but puddling on the floor means the seal is beyond redemption. Plugging the weep hole will stop the leak but allow coolant into the brg. Over time, the brg will wear from lack of lubricant....& fail. You could keep driving the car & monitor the brg for wear [ side to side slop ] but eventually the pump WILL need replacing.
 
Even the FSM says replace.

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Ugh, that’s gotta be frustrating!

I think since you’re asking, deep down you know the answer.

Your attention to detail, based on your other “how to” projects on your Duster, is awesome. Keep up the stellar work by replacing that pump (again).
 
Plugging the weep hole will just make the coolant come out the end of the shaft and onto the pulley itself. This will throw coolant all over the place while driving.
 
Just a crazy shot in the dark as you are saying it is a b...h to change that new water pump.

Turn radiator cap 1/2 turn to allow pressure release. Rubber tipped blow gun with line pressure at 50 psi.

Remove fan belt. Apply air pressure into weep hole with blow gun rubber tip, while turning water pump/fan shaft back and forth by hand.

With a brand new pump with a brand new seal, there could be a spec of sand or internal engine corrosion that worked its way in between the new seal and shaft > coming from inside the water jacket.

See if you can back blow that weep hole cavity and dislodge the dirt between the seal and shaft, spinning the shaft by hand.

Worth a simple try before you dig into it again and buy more parts. It may stop dripping.

Good Luck....


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I've always understood that the bearing is going or has gone bad once it is "peeing" out the weep hole.
The pump does have a porcelain face seal and as mentioned could have dirt stuck in it. Air would be a quick and easy fix if you do as stated above. I never thought of that but will be my next try if I have the same problem. Post #19 is a great idea
 
I have also seen (on a Ford 5.0 non HO) the water pump shaft "walk back" and push on the sheet metal backing plate causing noise and a leak.

But yeah leaking out that hole means replace i guess you could play around and get a few more miles out of it in "combat conditions" once you hear the bearing though its done. Ye s they make noise when toasted.
 
example: 2002 Dodge Ram 360. Notice a small amount of coolant dripping from the water pump. Headed to a shop to have the water pump replaced. Carried along 2 gallons of water in case the coolant wouldn't make the 10-mile trek, and it didn't. 1/8th of a mile from the shop and the truck began to overheat. Pulled over, added 1 gallon and made it to the shop. Strangely, the leak stopped and other than the residual coolant from removing the cap to add water, the leak from the weep hole ceased. I decided to head back home without replacing the pump. 2 months driving without so much as a dribble I decided to dump the water contaminated coolant and replace it with a fresh few gallons of antifreeze. Mission accomplished and still no leak. One hour later started the truck and lmfao, eureka, the leak was massive out of the weep hole. Needless to say wasted coolant and new water pump installed. Some crap plugged the weep hole when the truck over heated 2 months ago and I knew better, but lesson learned.
 
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