leaking water pump bolt

[piantm]

shaking out issues on a fresh rebuild of the 70 340. Water pump bolt is leaking, passenger side. Any ideas how to stop it.

 

[moparleo]

Remove the long bolts and apply a sealant like pipe dope or silicone. They go into the water jacket on the block and will leak if not resealed when you install a new pump.

 

[piantm]

thanks for the tip. That didn't work either. Felt the bolt never was tightening properly, and found damaged threads on the bolt. As if something was cutting into it. Pulled everything off the front of the block, found the bolt holes in the block are damaged. I'm able to wiggle a 5/16"-18 tap through the hole without turning it. Now I gotta try my luck at putting a heli-coil in. Never did that before. Any tips

 

[moparleo]

Just take your time and drill straight. It is not that hard and a good thing to learn. It will come in handy in the future.

 

[Chryco Psycho]

I may be hard to seal a helicoil , timesert would be a better choice

 

[piantm]

thanks for responses. Gotta hope the helicoil holds. Installed it yesterday. Had I seen Chryco Psycho response before I did the job, I may have used the Timesert. Looks like a good product. Maybe the next I get the pleasure of doing this job, I'll choose the Timesert.

 

[piantm]

OK, fix the thread issue with the helicoil. Now having trouble with oil pan to timing chain cover gasket staying in place. Numerous attempts ending with frustration and failure. The rubber seal is being pulled into the the oil pan as I tighten the bolts. Last attempt, I carefully tighten all the bolts gradually, the gasket held it's place. I then was putting the final turn on the bolts and suddenly the gasket sucked in on the drivers side. This has been my problem five times now. I'm doing something wrong. Don't know what. Any help out there?

 

[moparleo]

The oil pan on the 340 went through a change in 1970. Be sure to get the correct gasket as there are 2 choices.

 

[piantm]

got it fixed. Found out today, that I should install the front seal dry. Sealant on the ends where it meets the oil pan gasket and timing cover. I was using silicon sealant on both sides of the gasket along it's entire length. Plus I don't think I had the rubber nipple pulled all the way through the hole either. Now I hope it doesn't leak when I get it running in a couple days. Thanks for the help