Is there a difference in the valve stem seals from a mechanical lifter head (a '73 head) to a hydraulic lifter ('83) head? I ask because I pulled the valve cover to investigate and it appears that none of the seals I installed on the intake and exhaust valves are even covering the tops of the valve guides. The seals I'm using now are from a gasket set covering slants up to '80. The seals I removed from the '83 head covered the tops of the guides, and on my old head they are covered also. I'm sure this would explain most of my oil burning problem.....

Engines in good mechanical condition equipped with the floating umbrella seals don't burn oil. The ones that push down on the valve guide work fine too.

_________________
Joshua

Thanks. I want to know if there is a difference in valve stem seals though.

The "floating" seals are supposed to stop the oil when the valve is open and seeing vacuum.

Like Josh said, good motors don't burn that much oil valve seals or not.

_________________
Official Cookie and Mater Tormentor.

Both kinds of seals exist out there on the market. I'm not sure, but I think the "positive" type (pushes down overtop of the outside diameter of the valve guide boss) was original equipment on the '81+ hydraulic heads. You do know that an air compressor isn't necessary to replace the valve stem seals...right?

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

Yes, I have rope to stuff into the cylinders and a spring compresser. The intake seals I took off the newer head had to be pryed off, though the exhaust where the floating type. Compared to the old head, there is a huge amount of oil reaching the rockers, even though I used the same rocker arm that I had in my old head. The only difference is the aft bolt, which has smaller diamater threads and is shorter than the old one. Yes, I know my engine is tired....but not that tired.

Well...give it a shot, put a set of positive valve stem seals in it if you're pretty sure the valve guides are in good shape.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.