I have always had a can of STP next to me when I rebuild an engine. I paint
every bearing surface with it as I assemble the engine. This insures some
lubrication when the engine cranks the first time. This was recommended to me
by an aircraft engine mechanic-from what you say, it is evidentally an
excellent idea!!!
Jan Eyerman
(from back in the days when commerical airliners still had props!)
Jarrid Gross <JGross@econolite.com> wrote:
John,
I have always had this exact same issue on first time runs.
I suggest the following.
1) Never install the oil cooler and base till you have fully established
oil pressure, and have had the engine running.
2) Prime the oil pump by putting thick oil down the filter
base oil passages (straight 40/50wt). An un primed pump
would rather suck air from the high pressure side, then
raise oil from the sump. Only high pump velocities would
yield enough suction to lift the oil into the pump, which
you wont get cranking by hand (unless you prime the pump).
3) Crank the engine with the starter for no more than 20 secs
at a time (no plugs).
4) After finally attaching the oil cooler, connect 1 of the 2 hoses
to the cooler base, and use the raised second hose to backfill
the oil cooler with oil. Lowering it will make a mess, so be
carefull draining the surplus oil prior to reconnection.
The problem is this:
The oil pump only puts out about 8ccs of oil per cam rotation.
This is only 4ccs per engine revolution.
80 revs would oly be 160ccs of oil, which is not enough to fill
the cooler, but might have been enough to fill the oil galleries
provided the pump was primed and the cooler absent.
Getting the galleries full of oil is the most important thing
then adding the cooler, prefilled with oil makes short order
to get pressure when you restart.
Hope this helps.
Jarrid Gross
-----Original Message-----
From: owner-alpines@autox.team.net
[mailto:owner-alpines@autox.team.net]On Behalf Of John Slade
Sent: Wednesday, March 27, 2002 4:09 PM
To: List, Alpine
Subject: Oil pressure in new engine
I've got to a point where I am looking for words of wisdom. I have
installed the engine in my almost finished restoration, and have
attempted to get some oil pressure, with absolutely no results.
Situation is as follows:-
Engine was built up from a virgin factory 1725 short block, fresh from
its original wooden crate. Bearings etc were checked OK before build-up.
Necessary additional parts were obtained from a 1725 which I have been
running for 15 years or so quite satisfactorily. All new gaskets etc.
Engine has standard oil cooler fitted, and usual Ford type screw on
filter. Oil pressure gauge connected, rocker cover removed and rocker,
pushrods etc liberally oiled.
4 1/2 litres of Quaker State 10-30 added. Engine (less spark plugs) was
turned by handle for about 80 turns, in the expectation that some oil
might be moved around. Engine was then turned on the starter for varying
amounts of time, sometimes as long as 20 seconds. Nothing on the gauge,
and no leaks. Have gone through this routine several times...still
nothing. Removed the plastic gauge pipe at the rear of the block, and
dumped 200ml of engine oil down the pipe in the hope of some of it
reaching the oil pump for priming purposes. Turned the engine on the
starter and still nothing.
Any suggestions?
Thanks in advance
John Slade
Manotick, ON
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