Solved: a pesky water pump leak

[dleapon]

After a long winter of replacing the head on my 1981 Spider 2000 I fired it up and it started and ran on the first try. My elation didn't last long as I noticed a trickle of coolant leaking from the water pump where it mated with the block. I hadn't touched it during my rebuild and it hadn't leaked before. I drained the coolant and removed the radiator-- and yes, this was right after I had refilled and reattached the radiator after the head rebuild. Suspecting a failed gasket I replaced the water pump/block gasket and the heater tube gasket. I used aviation-grade gasket sealant per forum advice, put thread sealer on the bolts that screw through to the water jacket. I even replaced the copper washers. I put back the radiator again, filled and bled the coolant (again). Started the engine and after a few minutes... a trickle of coolant reappeared!

I had one desperate hunch, I remembered that the bottom water pump bolt seemed to wobble more than it should when I was screwing it in. I decided to try replacing just that bolt with a stainless steel bolt. That did the trick, no more leak. My guess is that the bolt (and/or the block thread) had corroded enough to where even the tread sealer wasn't sufficient to block off coolant. Not sure if anyone else has run into this situation but it seems worn bolts that are exposed to coolant might something to consider when chasing down water pump coolant leaks.

[GreyDR]

Good to hear it was an easy fix. My uncle is looking to get this Spyder 2000 project with a coolant leak and idling issue. We'll take a closer look next week after we finished installing the bumper and shocks from 4Wheelonline onto his current Wrangler project.