Re: Oiling system history recap and update on the Oldsmobile oil pump conversion

Posted by Scott On 2024/5/22 15:10:40

On the upside, with the standard Olds Melling pump with stock relief valve spring (it came with a "high pressure" spring for optional installation), I've got great oil pressure on my formerly rebuilt V-8 and the lifter ticking is now gone. I did not opt for the high pressure spring as I expected it would not increase idle pressure but would boost the higher rpm pressure more than really necessary. I'm observing a steady almost 3/4 scale indicated pressure on the gauge at all rpm.

One surprise when I disconnected the internal vacuum tube to the vacuum booster is that it was mostly full of engine oil. The oil pump bushing appears to be tight, no play. I've not yet disassembled the original pump but am thinking the air ingress is from the vacuum booster rather than the shaft.