Scott-
The oil pressure relief valve, perhpas? A weak spring may be limiting the
pressure to 55 or so. When you blip the throttle, the temporary increase
in pressure causes the valve to open, relieving the pressure. You
mentioned that you are running a real light break-in oil right now. I
would expect closer to 75 PSI once you replace it with the 20W-50. My B
has about 70,000 miles on the bottom end. I run consistant pressures of
around 50 PSI hot idle, and 75 PSI @ speed.
Regards,
Chris Delling
At 10:37 PM 9/10/97 +0000, Scott Gardner wrote:
>Well, I'm going to have to ask this again, because even with the
>complete rebuild, the gauge is still acting up.
> I have a 72 'B', and when I'm cruising along with the oil pressure
>reading about 55 psi, if I step on the gas, the oil pressure will
>momentarily "snap" down to 50 or so, and then pop right back up.
>Today, it actually did it while idling. I sat there and watched the
>needle snap back and forth between 50 and 55, about once per second.
>I guess I never noticed this at idle before because prior to the
>rebuild, the engine would never idle at 50 psi (more like 15). I
>could explain the needle snapping up or down if the needle got stuck
>and suddenly broke free, but cycling back and forth at idle has me
>puzzled. The engine tone never changes, and this phenomenon always
>occurs right around 50-55 psi. Before the rebuild, it would happen
>most often as I accelerated. The oil pressure would rise to 55, and
>then drop like a stone to 50.
> Since everything in the engine except the rocker shaft, rods, and
>pistons are new, am I looking at a bad gauge? There are no oil
>leaks (at least external ones), and oil consumption has always been
>very low. I'm half tempted to buy one of the Sunpro $12 oil presure
>gauges and hook it up. Is the oil fitting in the block a standard
>fitting?
>
>Scott Gardner
>gardner@lwcomm.com
>www.lwcomm.com/~gardner
>
>
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