Good morning folks. Ok, I've got a 9N #5222 which is running pretty well. Still can't get a lot of rpm's out of it. Bogs down when attempting to advance throttle. That's not my big problem though. I'm showing no oil pressure. I took off the lines all the way to the bottom of the filter canister and they are all clear. There is very little oil in the canister. It's not knocking when running. A little bit of noise from what sounds like the valves. I ran it about a mile bringing it home from my friend who solved an ignition issue for me. I wasn't too concerned at that time about no pressure on the gauge as I thought maybe a blocked line. Any suggestions on how to determine if I have a serious problem? How much oil is supposed to remain in the oil canister when shut down? If it appears to be an oil pump issue, do you have to split the tractor to fix that, or can you just drop the pan?
Everything else on the girl works well, (e.g., pto, transmission, and one brake!LOL!!) Thanks in advance for any help.

On the front of the engine, above the dist is a 15/16" hex bolt head.
Remove that and add oil to prelube the pump.
Now if your lucky, your bearings might have survived that trip.

I have seen an engine intentionally drained of oil.
It was an obsolete engine and on a stand and had to be destroyed for disposal.
An hour later it was still running and no noise and not slowing down.
If memory serves, it was running at full throttle.
Ford 200 straight 6 with a draft tube.

Smarter people than me should be along shortly.