2.2 liter cavalier, losing all oil pressure?

[dave36256]

Just built a 2.2l OHV. Crank turned to .020 main, .010 rods. Installed new sealed power mains, inserts, rings. Block was vatted, cylinders checked deglazed. When it started had about 50ibs of pressure. As it got hot slowly fell till it was at 0. When you race up engine comes up to about 30 lbs, falls when rpms fall. Any ideas. Cracked block? Motor stacked insert to start with due to low oil pressure. Also has a new meiling oil pump.

[sharkey]

how were your bearing clearences??? what oil is in it???

[dave36256]

clearances were about 2 thousandths. A couple were a little more. That was with the plastic gauge. Oil is castrol 5w-30, oil filter is purolater pure one.

[geoffinbc]

Is the pressure relief valve installed and with the correct spring? Where is the oil pressure being read? What type of filter is in the block? Was the filter bypass removed?

[85_Olds_Ciera]

When it started had about 50ibs of pressure.
...meiling oil pump.

It may be by-passing....today, on a 150,000 mile GM pump, I pulled plate off and used shop air set to 50 psi, and pump's bypass circuit was engaged.

Pump looked fine...I suspect something got stuck in bypass circuit...or spring went kaput...haven't had time to figure it out...putting new pump on.