You're getting oil smoke under high vacuum conditions, which may well be
separate from the compression issue.
Deves rings have a scraper (tapered) edge on the top compression ring which
must be installed pointing downwards, otherwise it will try to scrape
cylinder wall oil up into the chamber.
You mentioned valve seals but how are the guides? If the guides are worn
you could get some oil leaking through even with new seals.
You're leak down test must be done with the piston at TDC on the firing
stroke. If it's anywhere else you don't know for sure that the valves are
closed. Do that test again, keep the piston at TDC with valves closed and
listen for air leaks at the carbs (leaky intake valve) the exhaust (leaky
exhaust valve) and the oil filler cap or crankcase vent (bad rings).
Bob mentioned that running rich can be a problem as a rich mixture can wash
the cylinder walls removing lubrication from them and causing excessive and
uneven cylinder wall wear. It is also important for the cylinder wall hone
to have been done properly for the rings being used. The stock rings are
chrome while the Deves are cast. Did the machinist know that?
How much larger was the ring end gap when the rings were installed in the
bores? My .040 over Deves rings were too long and I had to file the ends to
get the correct gap on all eight of the compression rings.
Other thoughts?
Brian '69 2000
Tampa, FL
http://web.tampabay.rr.com/oilleak/
-----Original Message-----
I have been off the list for several months having finally gotten my
roadster back together and getting other projects finished. But after
driving it now for several months, I'm seeing blue smoke out the tail pipe
as described below.
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