Jack,
When you say "crank rods, mains, cam bearings checked to spec", does that
mean that after 42 years of use it was thought they were within acceptable
tolerances, or were they in fact turned and new bearings were installed to
suit?
Many years ago I rebuilt a 3000 engine and the machine shop gave the
journals a "polish" which I was told would only be a thou or so. The result
was about a 5 lb. loss of pressure across all ranges.
I would suggest the tolerances of the journals vs. the new bearing shells be
checked. It's likely these journals would have been better with a turning to
the next appropriate size, with bearings to match. A new pump, or at least
dressing the bottom surface of the alloy pickup plate the steel gears run on
would be adviseable. Also install a new oil pressure relief valve and
spring.
Rich Chrysler
----- Original Message -----
From: "Brashear, Jack, N" <JNBrashear@garverengineers.com>
To: "Healey List" <healeys@autox.team.net>
Sent: Wednesday, May 19, 2004 4:23 PM
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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