Headbolt

[supereal]

The problem with "wet" head studs is often related to the use of a threading tap to clear the threads in the block, instead of a proper cleaning tap. Old cast iron is very fragile from years of hot/cold cycles, and the threads can be damaged. We use a good clearing tap to clean the block, and put sealer on the block end of the studs. New studs are a "must". As for Barr's Leaks, the "factory rebuilt" engines always included some, and seldom caused problems.

[Pete]

Originally Posted by supereal

The problem with "wet" head studs is often related to the use of a threading tap to clear the threads in the block, instead of a proper cleaning tap. Old cast iron is very fragile from years of hot/cold cycles, and the threads can be damaged. We use a good clearing tap to clean the block, and put sealer on the block end of the studs. New studs are a "must". As for Barr's Leaks, the "factory rebuilt" engines always included some, and seldom caused problems.

You should use a common standard class 3 tap for cleaning block threads. It will put the threads back to original and bare metal if they have been distorted.
You CAN NOT get an accurate torque reading with rust and scale in the threads.
You should test the threads when the block is in the machining stage, NOT when you are installing the heads. If one pulls out, it can be repaired without getting chips inside the engine.

As to Bars Leaks, listen to KIWIinUS. (post #5) The NEW stuff is no good.