Well.. I disassembled the pump and I found one problem - I drilled too far through the venturi:
And you can see how big the hole is:
1) Is this damage repairable? If not, recommendations?
2) If I drilled all the way through, we would expect to see much lower idle pressure, no?
A couple of other disassembly pics:
I don't recall this strainer being so black before....
And where did all this crap come from?
I am going to reinstall without the black venturi just to see the test result. Will report back in a few.