Miata Mailing List: June 1994, Message #208
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   From: a.mccombs3@genie.geis.com
Subject: cylinder oiling!
   Date: Thu, 9 Jun 1994 21:28:32 -0400

I used to make my living in aviation, and one outfit I worked for flew DC-
3s, with big radial engines (like 14 cylinders and 1830 cubic inches each -
that's 30 liters displacement we're talking, but if you want to get picky,
the nine cylinder 1820s were the worst).  The bottom cylinders would
normally have oil run into them, seeping past the rings, even though they
had dry sump lubrication (there would always be some oil in the case and
lines, which would flow down into the cylinders).  Standard procedure before
starting, and a couple times a week even when not flying, was to turn the
props over by hand to make certain there was no hydrostatic lock in any of
the cylinders.  This was a lot of fun in WI in January, when the straight
weight 50 equivalent oil was like tar, and the ramp was covered with ice.
There were a couple airplanes which would regularly fill one or more lower
cylinders with oil, so one always carried a plug wrench.  Naturally, you
would be standing downwind when the goo started flowing from the plug hole.
It might have been tarlike, but it would still blow around a bit.  Naturally
 this was the day you were scheduled to fly the trip.
 
Anyway, it never occurred to me that a Miata could have hydrostatic lock
problems in common with a clunker like a DC-3 - no matter how it's
maintained.
                                                --Jack M.--