Jack's question triggered a question from me - the reference to the 1/4"
nut behind the relief spring. Is this intended to boost pressure, and if
so, does it work?
My BJ7 probably has 10 to 20k miles on a rebuild (not by me) and the oil
pressure readings are similar to or lower than Jack's - fairly high on
startup (with 20-50 oil) but probably maxing out in the 25-30 psi range
once the oil warms up, and dropping even lower at idle.
By most accounts, this is on the low side, and some people have
suggested just replacing the bearings from below. I'm more inclined to
drive it until something breaks and I'm forced to yank everything,
including the tranny that needs a rebuild anyway. But does this "nut
behind the relief spring" fix achieve any tangible results? Or would a
new relief spring help - have no idea if mine was ever replaced, but it
quite possibly was not
I've also heard that oil "flow" is more important than pressure - that
as long as you're getting good flow, and the bearings aren't knocking,
you shouldn't worry. True?
Thanks.
-Graham
-----Original Message-----
From: Brashear, Jack, N [mailto:JNBrashear@garverengineers.com]
Sent: Thursday, May 20, 2004 4:24 AM
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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