Dave Hyde wrote:

Anyone got any suggestions on how to pre-oil
a Lyc. O-320 before its first run?

Dave 'it might just be a train' Hyde



Dave,

Lycoming's service instruction 1241c (still active) addresses the
subject of pre-oiling after overhaul,

http://www.AirplaneZone.com/NewsgroupPix/si1241c-1.gif
http://www.AirplaneZone.com/NewsgroupPix/si1241c-2.gif

I'll leave that SI up for a few days. As Wayne correctly noted, and
assuming you have just overhauled your engine, the assembly grease
that you hopefully put on your cam lobes and follower faces will
last through pre-oiling and engine start even if the engine takes long
time to crank up. When you assembled your oil pump you should have
"primed the pump", as it were, by drenching the installed impellers
with engine oil.

When I overhauled my Lyc O-320 many moons ago, I hand turned the prop
(no spark plugs in cylinders) with the line to the oil cooler
disconnected until oil started to flow from the line. Then, as per SI
1241c, I pre-filled the oil cooler, attached the oil cooler line, and
cranked the engine with the starter until engine oil pressure showed
on the cockpit oil pressure gauge. Pressure came up in less than 5
seconds. Then I put the plugs back in, did a final check, turned on
the electric fuel pump, did another check for fuel leaks, and fired up
the engine while a buddy stood by with a fire extinguisher watching
for leaks etc.

Have fun!

David O -- http://www.AirplaneZone.com