bad valve stem seal questions?

[berrett]

i recently got a 1980 toy truck with a 20r with 142,000 that has been sitting for a couple years. i pulled the plugs and two of them had a bunch of oil on them. the previous owner thought a ring was bad and that is how the oil got in there. i did a compresion test and all 4 cylinders and they each had 150 psi. my buddy mentioned that maybe the valve stem seals were bad and causing oil to leak down into the cylinders. does that sound like what may be happening (don't know much about motor internals) and how hard is it to change them, can you change them with the head on the motor, or do you have to take it off? any tips or tricks that would help, or any other things to check on these motors that may be causing the problem?

 

[Brad J]

can you change them with the head on the motor, or do you have to take it off? any tips or tricks that would help, or any other things to check on these motors that may be causing the problem?

The heads have to come off to do any work on the valves. I had a machine shop work on mine when I rebuilt a 350 years ago. Depending on the position of the cam some of the valves would be open = letting a little oil inside the cylinders. That would be my guess. I would probably run it as is after getting oil pressure up, w/ plugs pulled. Then firing it up and see how it does, but I don't know anything about Toyota motors

 

[I Lean]

I agree, run it before you do much to it. The 22r is a reliable motor, but known for bad valve stem sealing---all that usually means is a puff of smoke on startup though, and probably a little oil usage between changes.