Index Home About Blog
From: John De Armond
Subject: Re: Oil Priming an LT1?
Date: Tue, 10 Aug 1999 18:03:00 EDT
Newsgroups: wrote:
> Yeap, what I was thinking to do was to squirt some oil into the piston
> chambers of all eight and disconnect the fuel pump relay (pull the
> fuse) and crank it for a while. But this, I think, could still be to
> hard on an engine that has been sleeping for so long. I was looking
> for other solutions.  Any of you guys ever heard of preassure priming?
> I don't know how it works, but I believe it involves compressed air.
> And of course there is the external electric pump, but last time I
> checked it was in the upper $400. (not an option).

I have a rig I use on all new engine starts.  It consists of a
stainless steel 5 gal Coke syrup can equipped with a schrader air
valve, a hose, a ball valve and a check valve.  The tank is filled
with 2 gallons of oil, pressurized to 100 psi and the end of the
hose with the check valve and ball valve is screwed into the oil
sender port.  Or in the unusual event the sender isn't easily
accessible, I use a modified freon side tapper to pierce the side of
an oil filter and tap in there.

In use, the can is sat on  refrigerant scales  (just because I have
'em), the ball valve turned on and when the scales indicate about a
gallon of oil has flowed in the engine and oil is visible through
the oil filler hole, the engine is fired.  The oil is allowed to
continue to flow until the scales indicate the proper quantity of
oil is in the engine.  The 100 psi air pressure in the can will
override the oil pump and lift its relief valve at fast idle.  The
check valve prevents any oil from being pumped back to the tank in
the event the air pressure is too low.  When the correct amount of
oil is in the engine, turn the ball valve and continue with the cam
break-in procedure.

The advantage of this procedure is a) it's cheap - the tank can be
had at flea markets or even from Coke, b) it fills the filter, the
galleys and primes the pump, c) one can verify proper oil flow
BEFORE firing the engine for the first time, and d) you don't have
to fool with any sort of priming tool and the attendant risk of
damage to the engine or of dropping something down the hole.

If you don't have scales, you can simply put the correct amount of
oil in the tank and flow it in until you see bubbles in the line
indicating the tank is getting empty.  I use the fabric reinforced
plastic hose that the coke company uses.  If that is not available,
one can use the clear fabric reinforced PVC hose available at Lowes,
Home Depot and the like.


Index Home About Blog