I had bought an aftermarket water pump and the opening at the top where the crossover pipe fits in is slightly off from where the original was. When I set the crossover pipe in place, it was wobbly loose against the heads. I had to double gasket where the crossover meets the heads to alleviate that issue.  A rubber o-ring is used to seal the crossover to the water pump. This was a poor design from the get go. I put sealer around the front of it, but found a leak on the back side. Can't get my finger back there to apply any. I ended up just squeezing some to the back side and used a screwdriver the best I could to smear it around. Held tight for about 200 miles and now it has a fine spray of a leak on the backside. I need to get this resolved before going on a long trip. Any suggestions from anyone else that had the same issue? I figure i need to spray a lot of  carb cleaner to clean the surface the best I can and add more sealant. Just getting to it is definitely going to be challenging. 63 Sedan DeVille.

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Andy, the pump is junk. The hole is drilled wrong. Get a new water pump.

We all use 2 O rings and a small amount of sealant.  Too much will just be pushed down into the water pump.  Put the O rings into the water pump, then install the manifold.

Not what I wanted to hear, but I guess I needed to. Thanks. I only used 1 rubber o-ring. I pushed it onto the nipple of the crossover manifold, then set it in place. I don't recall from where I got the water pump off hand- guessing it was a remanufactured one? Any suggestions where I can get a replacement? I haven't begun to look yet. gotta let it sink in. if it's not one thing, then it's another. 

Even though doubling the gasket on both sides of the cross over manifold got rid of the shimmy wobble and made for a snug fit against the heads, it may be possible, then, to keep the water pump and just add the 2nd o-ring to the mix. It would be a lot less work and may resolve my issue. I thought there was simply an extra o-ring in the kit. Going from memory, it seems as if they may have been just ever so slightly different in size from one another.

Get the water pump with this design impeller. Cardone select at rock auto.
Oh no....

This is what I have from Rock Auto (Gates)
You can try to use a cooling system sealer called Alumaseal ( aluminum particles)
Using it for 40 years sometimes more than one with super results
It should fix the problem until you can get to it and possibly permanently
Would be a quick fix

Do take Russ's advice and get the pump that Clovis is recomending and all will be fine with you project
These guys know there stuff !

I just do not like the fact the WP does not line up with the water cross over in this case

Use two washers with a product called Permatex applied to them
From the auto store
It dries fast and will not leak
Used that combo on my last two water pumps with perfect results long term
My car is with me 50 plus years so thats the reason for requiring the two WPS


Tony- when you make reference to two washers with Permatex applied to them, are you referring to the rubber o-rings where the water pump and crossover manifold mate together?

Hi Andy,

I did this job last week and because I didn't look hard enough, I managed to crack the crossover assembly. Its easy to do, so steady freddy is the way to do it. I used 2 rubber O-rings and the blue permatex silicone sealer.

When I was doing up the 4 bolts in the cylinder heads, they went nearly all the way by hand and I hadn't applied much pressure when a very audible CRAAAAACK went off.

Make sure the crossover is sitting level and has gone all the way into the water pump.

I don't think crossing your fingers and toes will help.... but hell.... it can't hurt either.

Andy, you can try to use 2 O rings with the same water pump. Just be sure to set the O rings into the water pump cavity.  Use some RTV sealant sparingly around the O rings.  Too much and it will push into the water pump.   Let the completed assembly cure overnight before you add coolant.  That's the hard part, waiting.

You cam also try a standard home water hose washer with a little sealant. Let dry and use O ring and reassemble. Worked good for me



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