Jinma 304 tractor was running with low pressure at idle. Now no pressure at all.

[quicksandfarmer]

Quicksandfarmer: Was it the driveshaft to your oil pump that failed? I had my cam shear in half on my 354 (which basically had the same result -- no oil pressure).

When I immerse my oil pump and run it using a drill, it seems to pump oil well. I just don't want to put this thing all back together and have the same problem...

It was the driveshaft to the oil pump. It sheared off right below the gear, clean in two.