Are you on a straight or a curve when this happens? Or does it matter? I
had a similar problem once during hard cornering, and installed oil pan
baffles to prevent starvation. I have a feeling that you have this
eventuality covered though..............
Randy Kegg
1958 MGA
1966 Morris Traveller
1964 Porsche 356C
On Sun, 13 Oct 1996 20:06:41 -0400 BarneyMG@aol.com writes:
>The facelift on my MGA crankshaft is complete and looks fabulous.
>Like
>magic, the rod journals are now standard size again and you couldn't
>tell it
>from a new one. Got it all back together with new bearings and went
>racing
>today. Drove it 135 miles from Naperville to Peoria, everything
>grand, and
>the weather was absolutely superb. So much for the good news.
>
>The race date lasted just 20 seconds into the first lap. Just got the
>engine
>up to 6 or 7K rpm for a few seconds and the oil pressure dissappeared
>again.
> Noticed the symptoms right away this time, power loss, huge drag-down
>effect, got off the throttle right away. A glance at the gauge showed
>it
>practically pegged at ZERO, then it recovered, right back up to the
>normal 62
>psi. Race day over, I nursed it off the track and put the streeet
>tires back
>on. No question about oil level this time, it was right on the full
>mark
>before and after the incident.
>
>End result is oil pressure at 800 rpm idle is now 20 instead of 50,
>and it
>takes up to 2500 rpm to reach pressure relief at 62 psi rather than
>1500 rpm.
> Still runs quiet, drove it home 135 miles at 50-60 mph, no change in
>status,
>figure the fresh crank is probably not damaged this time, just in need
>of a
>new set of bearings.
>
>Now the technical stuff. Fresh crankshaft, all journals reground, all
>sizes
>perfect by the micrometer. All new bearings, correct sizes, checked
>by
>plastigauge for correct clearance. Cleaned all inside of engine
>before
>reassembly, checked all oil passages in block and in crankshaft.
>Proper oil
>restrictors installed in rod journals of crankshaft. Had disassembled
>oil
>pump for inspection, pickup tube and housing clear, screen clean,
>internals
>of pump in good condition, cam gear OK, pump drive gear OK, pump drive
>tang
>OK. Before starting engine, 30 seconds cranking on starter only with
>spark
>plugs removed produced 50 psi oil pressure (yes, just at cranking
>speed).
>
>So, come forth ye wisdom of the list -- puzzle of the week -- what
>happens to
>my oil pressure at 6000 rpm?
>
>Barney Gaylord -- 1958 MGA
>
>
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