I replaced a waterpump on my '73 F-100 (302 2V) this spring as the impeller seal was leaking. Everything good, all summer, no worries. Yesterday, going out to enjoy a nice day in pre-salt November, coolant pooled behind the waterpump on RH side of block after allowing the engine to warm for 10 mins. Figuring a heater hose or the bypass was leaking, thought no sweat, easy to fix. Neither were leaking, leaving me to wonder whether the plate on back of new waterpump is leaking, or, is it something worse, like a cyl head gasket?

I've been a GM guy prior to this, so any direction would be great, as ripping the waterpump off prior to getting advice on where to look first probably isn't the best idea....

Thanks!

 

If its not the by pass or thermostat housing, then chances are its the timing cover gasket. Coolant runs through block, cover, to pump. Every time a water pump is replaced, the gasket gets a little weaker. If you have a pressure tester, you can confirm the leak. Removing the cover isnt a hard job, but does take some time. Unfortunately the new pump has to come off again. Thats why I recommended a pressure test to be sure whats going on.

 

Thanks for the advice, I wondered about that being an issue as well. If I need to remove it, is changing a cam in a 302 as easy as doing so in a Chevy 350?

 

Yes, a cam change is pretty straight forward. If its non roller lifters your using, make sure you use a proper break in oil. Regular modern oils dont have the wear barriers for the non roller type.