Late Model Flathead Blow By

[Henry Floored]

What viscosity are you running for oil? If you do have true blow by and your compression test checks out rethink your oil choice if you are running heavyweight oil.

I was told by a Hastings Piston Rings engineer that we can overwhelm the ability of the rings to maintain a "seal" against the cylinder wall. She explained to me that the rings when faced with too high a viscosity (too thick) the rings can sometimes actually hydroplane on the film of oil on the cylinder wall. This leaves oil to get past the rings and thus be burnt in the combustion process.

If this is what you're experiencing I suggest 10W40 oil alone, no other additives. It would be nice if it was that easy. Right? Believe it or not there is a good chance that's all it is.

Good luck friend.