Hi Jack,
Rich is absolutely correct in his assessment.
The only comments that I would add are that the nut under the oil
pressure relief valve spring will only increase the oil pressure when
the engine is cold. If the engine is a little worn the relief valve will
be fully closed when the oil is hot.
You can check this once an engine is heated up by installing a piece of
bar instead of the spring and tightening the external nut just enough to
solidly seat the relief valve (there will be a bit of a leak past the
threads but that's ok for the test). My bet is that the hot oil pressure
won't change one bit.
I have also found that changing cam bearings on a high mileage engine is
essential if you want to get good oil pressure. 30 p.s.i. at 3000 hot is
pretty low, but we had one customer who ran his BJ8 with under 20 p.s.i.
hot at 3000 for years and it was just like that battery bunny on TV. I
think he kept driving it that way because I kept telling him it was
going to blow apart some day...as far as I know he's still driving it
the same way!
Michael Salter
www.precisionsportscar.com
-----Original Message-----
From: owner-healeys@autox.team.net [mailto:owner-healeys@autox.team.net]
On Behalf Of Brashear, Jack, N
Sent: Wednesday, May 19, 2004 4:24 PM
To: Healey List
Subject: Oil Pressure Questions
Hi All, I've owned the same Healey since new for almost 42 years but
there's always something you don't understand about your own car. It's
a BT7 Mk2 with the 29E engine and less than 400 miles since rebuild and
with oil pressure that's too low for my comfort zone. The rebuild
includes new rocker shaft and new bushings and literally everything else
new. Crank checked to specs on rods and mains, cam journal bearings,
etc. all check to specs. I have a Smittys spin-on oil filter adapter.
I have tried oil viscosity extremes from GTX 20-50 to Valvoline racing
straight 60 wt. I have a 1/4" nut behind the relief spring. The oil
pressure is pretty good at about 65 psi at startup but drops to just
under 30 psi at about 3000 rpm on he freeway at about 180-185 degrees
temp. The oil pump also checked to specs so I DID NOT replace it. Is
there a HIGH PRESSURE oil pump available?? Do I need such a thing??
Does HEAVY DUTY mean the same as HIGH PRESSURE?? I'd appreciate some
feedback from this awesome list. Thanks Much!!
Jack
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