we almost were ready to fire up my buddys rebuilt 351w and when we put the anti freeze in we noticed it was leaking from the lower head bolts on each bank?? its a 70s block he had someone rebuild it with new edelbrock heads

 

did you use thread sealer?

 

The lower head bolts don't reach the water jacket on a 351w like a 302. At least they didn't on mine.

 

oh, see i learn something every day

 

From what I hear it's just the 5.0 blocks that need sealer on the lower bolts. Just checked the 70's 302 block in my garage and they don't reach the water jacket either.

 

my block is a 71 and it had sealer on it from the reman job done before i took it apart but i did not check the depth, maybe they just use it as a fail safe