Chris, thanks very much.  With your information I now understand how that hole plug works.

However, there is already a plug in the hole.  I thought the problem was that I could see through into the crankcase.  But now I understand that is not a problem.  And the plug that is in there is not leaving any small hole, to the side within the big borehole, uncovered.

So that would not be the reason for my front main seal oil leak and marginally low oil pressure.


Therefore I'm back to trying to find the real reason for those problems.

As one possibility, I'm looking at the governor bushing.  I replaced that during the overhaul with one I got from Korves, and I used a tool from them
to drive the new one in to the correct depth.

I do notice that the new one has a small oil channel, all the way front to back on the inside, maybe 1/8&quot; wide and 1/16&quot; deep.  At the bottom of this is a small hole to the outside of the bushing.   Also there is a small hole opposite this, through the bushing.

I would guess the channel and holes are correct but wanted to ask.

Secondly involving the governor bushing, I know the service manual instructions say to drive the bushing in so that one of the sleeve grooves (groove on the outside of the bushing, I think) is in line with the oil hole drilled in the crankcase.   I recall in the overhaul driving it in and thinking I had not made that alignment.   

Even if that's true I think I would be getting less oil out there, not more.

As I mentioned, I could go back to the dealer and get the timing gear cover that I bought then returned, and assemble things with that.  Maybe that's what's needed to stop the oil leak.  It would not seem to explain the oil pressure problem.

By the way, my old timing gear cover is heavy stamped sheet metal, not cast iron or aluminum. The Oliver mechanic I talked to said he had not seen one like mine.  However, I did not have an oil leak there all the years before the overhaul.

Thanks again for any ideas you have.  I really appreciate your help.

Tom