Jack -
Another thing is the gear pumps aren't so great for maintaining
pressure at lower RPMs when the oil gets warm. The older Rotary Vane
pump is much better, more reliable, and pumps more oil at lower RPMs
than the gear pump. BMC replaced it with the gear pump because they
are cheaper to make. Gear pump is also a little better for race
motors... other than that get a rotary vane pump from the UK... they
are much better and more durable for long term road use.
Regards,
Alan
On 5/18/05, Brashear, Jack, N <JNBrashear@garverengineers.com> wrote:
> Hi Folks, I can't seem to keep the oil pressure in my "comfort zone."
> 29E engine in my BT7 Mk2. I bought this car new and I've always turned
> my own wrenches so technospeak is OK by me. The engine is very fresh
> and has its second new oil pump recently installed. It doesn't seem to
> matter what oil I use...20W50 or straight 50 wt. Valvoline. Heck, I
> even tried straight 60 wt. once. Startup pressure is 65 psi with any
> oil. After spirited runs on a straight lonely road at 80 - 100 mph,
> running pressure at 3k rpm barely comes up to 20 psi regardless of the
> oil wt. All bearing clearances are correct. Could the relief spring be
> so weak that I'm bypassing all the time?? Has anyone ever jammed
> something behind the plunger to prevent its opening at all. Now I'm on
> my second new M+++ oil pump (gear type) in under 1000 miles. Are these
> ever so badly built such that the oil is bypassing internally?? What do
> you racers do to keep good oil pressure?? I have installed a spin-on
> filter conversion and I have an oil cooler that I could install if
> needed. This baffles the dickens outa me and I'm really hoping for some
> help from this awesome list. Many Thanks!!
> Jack
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