waterpump L-75 1964

[Stephen W.]

Well It was a great day and I couldn't wait to get home to give the Coupe some needed attention. Connected the battery and pulled and grounded the coil wire. Spun the engine over a few turns to get the oil back up where it belongs and fill the fuel bowls. Reconnected the coil wire and she fired at the first touch of the key. She idles up on the fast idle for a few seconds till I kick it down with a quick jab of the go pedal. Like meeting an old friend you haven't seen in a year. It just purrs as I engage the clutch and ease it out of the garage. Thats when my bubble burst. I spotted a puddle of green antifreeze where it was parked! I lift the hood and everything looks dry? Then I see spots of antifreeze splattered all over the 26 year old Daytona Blue lacquer! Now my perfect afternoon to go for a spring cruise turned into a chinese firedrill. Shut it off and hosed off the splattered antifreeze. I check every hose and find nothing. Radiator is bone dry on the outside with not a hint of seepage anywhere. I dry everything up and still do not see anything that waves a big red flag and says I'm leaking. I found a tiny ...and I mean tiny amount of dampness at the weephole in the water pump. It's hard to believe that much antifreeze could have escaped. I say this because the warm engine dryed everything up in a few minutes. I didn't see any additional antifreeze splatters and all seems to running dry? Water temp is right at 180? I took it for a short trip around the block and do not see any leaks?

1. Trying to keep the original pump I'm thinking of rebuilding it myself.
Has anyone here rebuilt their pump? Parts easy to find?

any thoughts on this?

[Joe L.]

Re: waterpump L-75 1964

Steve----

It's very possible that the coolant leakage was just due to the long period of non-use. The waterpump seal is a carbon/ceramic seal. Sometimes, especially after a long period of non-use, there will be some leakage at the carbon/ceramic interface. This leakage exits the waterpump at the "weep" hole. In fact, that's why the hole is there. A carbon/ceramic seal is NOT a 100% leakproof situation; there is a small amount of normal leakage.

However, if your pump has on the order of 50,000 miles use, it would not be a bad idea to rebuild it or have it rebuilt. Waterpump rebuilding is something that seems simple, but it doesn't always turn out right. Chevrolet included waterpump overhaul procedures in Chassis Overhaul manuals through about 1971. Then, the procedures were dropped and waterpumps were considered a unit-replace item. I believe that this decision was made due to the problems associated with field rebuild of waterpumps. Also, GM dropped most waterpump SERVICE parts about that time, too.

If you wish to rebuild your waterpump, you can purchase rebuild kits from most of the Corvette parts vendors. These kits include a new shaft/bearing assembly, seal, and backing plate gasket. These are all the parts you need.

Or, you can send your pump off to Bill Mock or Arthur Gould. They'll rebuild your pump and get it back to you promptly.