The oil pump turns about 1/2 the RPM of the crank, so a simulated idle would be about 500 RPM at the pump. The pump, if it builds 50-60 cold PSI will nearly stall a 1/2" drill. I agree with trying new gears first, then replacing the cover if needed, chances are you won't. End clearance is much more critical than side clearance, so get that right. Make sure the relief valve is free to move, and use a new spring (should come with the oil pump kit). Old springs weaken with heat and age, and the plunger could stick from varnish. You could also plug the filter bypass, or Bulltear makes a replacement cover/plug. Run a quality filter (I like Wix or Napa Gold). The new oil filter adapters don't even have the bypass machined. Think about Bulltear's HRC pump gear set. In my AMX and Rambler (also in the Jeep I sold) I ran the HRC gears, mid plate, and filter bypass plug. The Jeep and Rambler are on the original covers, the AMX has a nickel coated cover. None have any oil pressure problems with the mods above.

http://www.bulltear.com/catalog/inde...160985ef4f09af

Bob
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