I just finished putting my 511 B1 engine back together and fired it up today. Something was weird when I primed it, only got around 35psi and it never stalled the drill which has always happened. I fired it up and it only has 10 psi at 1200 rpm and gets very little more if you bring the revs up a bit.

I just pulled the front cover to make sure the plugs are in it. They are. I did that because it looked like one side rockers got alot more oil than the other.

I'm gonna check the relief valve in the oil pump but I had it apart before it went on and it was free.

This is a stock block 511, it has a solid roller cam with .760, .716 lift with 1.7 T&D shaft rockers. Maybe the lifters are uncovering the oil feed? These were supposed to be good.

Maybe I'll drop some solid lifters in it and see if it will prime with pressure.

Any other ideas?