1966 429 water pump

[dgll411]

My water pump has just gone bad. I am looking for advice on replacing it. I am most concerned about removing the bolts without breaking them. Any advice would be appreciated.  Thanks

[TJ Hopland]

Good you are asking for advice, I have heard things can go really wrong with these.  I don't have any hands on experience myself so I can't offer specifics.  Hopefully someone will be along to tell you what to look out for and options for dealing with those issues. 

I know the wrong thing to do is snap bolts and assume you can get a replacement timing cover.

[Chris McBride]

The forum for the 1963-1964 Cadillac website has a search function; a search for water pump will yield many dozens of posts. The 1964 429 and your 1966 are essentially the same engine. Your instincts are also correct since many of the posts deal with snapped bolts.

https://6364cadillac.ning.com/

See Mr. Edge's comment and advice at the following link for one discussion.  It's an older post - Jason had only disassembled 42 of these cars at this time (2014).  The posts are in reverse chronological order so start at the bottom.

https://6364cadillac.ning.com/profiles/blog/show?id=6543066%3ABlogPost%3A88850&commentId=6543066%3AComment%3A89799

Several recent discussions have also highlighted problems with suppliers of replacement pumps and concerns with impeller size as well as opinions concerning cast iron v. aluminum pumps.

I opted to send my pump to for rebuilding.

"My age is such that I now consider the water pump a major PITA to change.  It also involves bolts going into the timing change cover which is extraordinarily difficult to source. I therefore researched re-builders before I did the last water pump swap since I wished to minimize the chances of a part failure.  After reading the posts on the CLC website, I sent it Gould."

Hope this helps and good luck!

[Chris McBride]

https://6364cadillac.ning.com/photo/1966-water-pump-and-front-cover

[Cape Cod Fleetwood]

Reach out to John Abend on the "1965-1970 Cadillac Collective" on Facebook

["Cadillac Kid" Greg Surfas 15364]

Danny,
You are right to be concerned. There are many techniques for removing stuck, rusted in bolts and I don't pretend to be an expert on them.My experience with MY '66 was that even using extreme care, two of the bolts sheared off "mid bolt" and I had to remove the timing cover to get the stubs out of the block. That is not a deal breaker, but hopefully you can avoid it. As TJ is "hinting" at is there are essentially no good timing covers around, and they MUST be 1966 or 1967 to work correctly. Oil passages on others are different.
Greg Surfas

[TJ Hopland]

I assume the issue with these especially with their age now is its an aluminum sandwich?  Its a thick slice of aluminum (the timing cover) between 2 slices of cast iron (the block and pump)?  And the problem bolts are long and go through all those different metals and are a different metal themselves and why not add some special sauce (coolant) for a little extra corrosion action?

[dgll411]

Here's an update. All the bolts were removed without breaking. What a relief! My next question is what is the best way to apply the gasket and o ring. Some say blue silicone,  some say dry, and some say Indian cement.  It looks like the last application was some type of silicone, especially at the output o ring for the cylinder heads. Looking for the best method. 

[TJ Hopland]

I don't know if this engine has specific requirements but generally on a water pump I use a film of blue rtv on both sides of the gasket.  I don't try to do a bead,  I just smear it on with a finger then flip it over and smear the other side.  I use a scrap piece of cardboard for the process.

["Cadillac Kid" Greg Surfas 15364]

FWIW these motors pre-date the age of miraculous sealants and other than using something like Permatex 20539 (Indian head sealer)the gaskets by themselves are intended to seal the juncture between the waterpump and the timing cover. That said the O-ring is a different story since it is usually difficult to get right. A liberal application of silicone is called for to be sure.
Greg Surfas

[dadscad]

The concensus on the 63/64 chapter is to use 2 O'rings on the cross over pipe connection in the top of the pump. Put the O'rings into the top of the pump. Be sure that the cross over pipe nipple that seals in the O'ring isn't corroded or worn down. If it is, get a brass bushing pressed on at a machine shop.

[Julien Abrahams]

x2 on the advice of using two o-rings. I have replaced the waterpump in my '67 some years ago. After installing and removing it 3 times (because it kept leaking at the top connection), I decided for the fun of it just to try two o-rings. That did the trick.
To prevent the pipe from hitting the o-ring and therefore not sealing the bore correctly I dried everything throughly, then put a very small dab of blue rtv on the inside of one o-ring (really small amount) and installed both of the o-rings on the pipe connection. The RTV is just to hoold the o-ring and precvent it from coming off when you install the pipe in the bore of the waterpump.
Same goes for the connections on the block. It is a little fiddly work. I 'glued' the gaskets between the crossover pipe and the block on to the crossover pipe, let it dry some and then install the pipe. Otherwise those gaskets will keep falling off...Ask me how I know .

[dgll411]

Well finally all back together,  started her up and I have a stream spraying out at the head/tube connection on the passenger side. Looking for advice,  I used permatex grey waterpump sealant  to glue the gasket to the tube, waited a few, put a small coat on the head, and connected it. Let it dry for days.

[Julien Abrahams]

Are you sure that the gasket was not torn when you installed the pipe? Because of the awkward angle (it has to bolt straight to each head and the pipe has to fall in the bore at the same time) it is quite tricky to be carefull enough that the gaskets don't tear.
I would suggest to take it off, clean the connections thouroughly, install new gaskets with a small bead of gasket maker (did you use the correct type?) between the gasket and the pipe and on the other side (between the gasket and the cylinder head). Then carefully bolt it back on, making sure it seats properly at all three connectiones. Once it is bolted together, let it dry for about a day. Then start it and check for leaks.
Good luck.

[dgll411]

Are you sure that the gasket was not torn when you installed the pipe? Because of the awkward angle (it has to bolt straight to each head and the pipe has to fall in the bore at the same time) it is quite tricky to be carefull enough that the gaskets don't tear.
I would suggest to take it off, clean the connections thouroughly, install new gaskets with a small bead of gasket maker (did you use the correct type?) between the gasket and the pipe and on the other side (between the gasket and the cylinder head). Then carefully bolt it back on, making sure it seats properly at all three connectiones. Once it is bolted together, let it dry for about a day. Then start it and check for leaks.
Good luck.

I dont think I caught the gasket on anything. At any rate it is disassembled and cleaned. Waiting for more gaskets. I used the gray permarex for water pumps and thermostat outlets. This time I may go with the brown Indian head gasket cement.  What do you think?

[Julien Abrahams]

I am not familiar with the head gasket cement. But after a quick look up I read that it sets solid. Others will have to chime in on that. I used the blue permatex (but I am sure the white one will probably work just fine as it does not come into contact with oil or fuel).

[gkhashem]

I second the two O-rings, when I did my 1966 timing chain and changed the water pump it would not stop weeping coolant until we used 2 O-rings.

[dgll411]

I second the two O-rings, when I did my 1966 timing chain and changed the water pump it would not stop weeping coolant until we used 2 O-rings.

Did you use rtv on the o rings? Should I put it on the bore and insert the pipe with the rings on it?

[Julien Abrahams]

Where exactly is it leaking? Rtc on the o-rings should not be necessary. By using two o-rings, it should seal. I used just a small dab to keep them in place when installing the pipe. Otherwise they would come off easily.

[dgll411]

I believe it is resolved. I took it apart (again) only to find the o ring ripped and twisted. Im not sure how it happened, I did not force it in. Anyhow, back together for a 3rd time, no leaks. Next is the road test. Thanks for the advise.