I am helping a friend with his 1959 Ford F100 truck. It has a 292 Y-block.

The problem is that he is loosing cooling water. I found no leaks to the outside of the block. Pulled the valvecovers and they were full of white sludge. So the water is leaking into the engine.

The engine does not smoke when started so I think it is not leaking into the cilinders but into the block itself. So i pulled off the cilinder heads because I thought of a blown head gasket. But the (composit)gaskets show no signs of blown thru at all. The fire rings are all okay. I do not see any traces between water and oil holes either. Head gasket looks like it was clamped evenly at the whole surface. I can not find any evidence for the water leak.

I have to admit that I am not familiar with the ford Y-blocks because I'm more of a Mopar guy. (okay, please don't shoot me)

Are there any other posibilities of water leakage into the block? Is there a chance of a cracked head? Do these heads crack easy? The engine did not run hot according to my friend.

The only thing that I can think of is a leak between the water passages and the pushrod holes. But no signs of that on the old gaket. The head bolts were really thight. I had to loosen them with a 3 feet pipe on my breaker bar.

Do you guys have any idea where to search the leak?