Hello, I have a follow-up question to my oil pressure post back in May: https://www.ntractorclub.com/forums/nboard/messages12/259824.html

I ran my tractor for a couple of hours last Saturday, oil pressure was low, but good. Today I started it up and had zero oil pressure on the gauge. Gauge is new, no oil leaks, and the oil level is good on the stick. Did my gauge crap out, or is there something else happening?

Finally got around to checking the oil pump prime; put some 80w gear oil in there, but it made no difference. I unscrewed the tube from the back of the gauge, cranked the engine, and had no oil squirting out. Uh oh. I'm afraid I've been running it a little bit with no oil...but wouldn't that have locked up the engine? Either way, do I have an issue that @sjones mentioned, where the pump is disconnected, or is there something else I can check without dropping the oil and pan?

After doing what others have suggested, The next time you change your oil put your finger up into the hole and see if you have any wiggle on the oil pickup assembly. The pick up tube weld can crack from years of vibration at the oil pump and it can start to loose suction. My whole assembly fell off at the pump and it needed to be brazed back on.

Another possibility is that your oil pump has lost its prime. You can restore it by removing the oil pressure relief valve at the front of your engine and using a pump-type oil can with a flexible spout, pump about a cup of 90w oil in there and replace the valve and bolt. You need a 15/16" wrench to remove the bolt. Be careful to not lose the spring for the pressure relief valve when you remove it:

Was the engine noisy? If you had zero pressure, the engine would be knocking. If not, you can try another gauge and flush out the oil line first before installing the new gauge.

Thanks; I'll try to re-prime it. No knocking, engine seemed to be running fine.