My Ryobi has the same problem as nick?
What is the problem with the oil feed? I introduced 4LBS pressure to the outlet and loads of oil came back at me but then after a few minutes it stopped again. I wonder if crankcase {Sump} pressure helps in any way? I've had 40 years experience as a mechanic and I think I'm going to have to strip. If I find anything out I'll post it on this page.
Panda, March 2009