I already posted this on the '48-60 forum, but thought I might try here too. I submitted a thread a few weeks ago lamenting that my freshly re-built flathead leaked water out the exhaust manifold on the right side. After taking the head off, a high heliocoil was found. This was carefully shaved down, and the head was reinstalled and torqued, but it still leaks at the exhaust manifold. All the sparkplugs are dry, so I don't think the heliocoil is the issue. A new manifold was installed, and it's not backwards. Could my block be cracked by the exhaust manifold? When you fill it with water, everything is fine until it is about 3/4 full, then it starts pouring out. The engine has never been fired up, so it's not an expansion thing. If the head were cracked wouldn't the problem only manifest itself when the engine were hot? Any ideas???? Tomorrow we will take off the right water pump to look for anything obvious, but I'm not feeling very optimistic right now. This really s___ks!!!

 

id hate to say yay or nay on the cracked block, but id lean toward the crack. But hey, what do i know? Ive been wrong before

 

If it has a cracked blocked wouldn't it have to heat up quick and bad?

 

not necesarily, it couldve been a crack in the block before the rebuild.

 

If it is cracked, Call Kelly's Block Welding in West Los Angeles/Culver City. Kelly, founded the place in the 1940's (maybe 50's) and during the war he welded up the engine blocks on the navy ships- incredible skill. His son Dennis has the shop for the past 20 years- he's even heliarc'd up a aluminum head that was cracked in 3 places clean through (racing ya know!)- never a leak in that 10.3-1 CR/180 psi in the cylinder engine!!!!!!