I was blading snow the other day and lost oil preassure on my 333. Had 40 lbs of pressure during warm up. I checked the oil level and it was about a quart low, added oil and start tractor again for about 5-10 seconds and still no pressure. Check oil level and new oil is showing about old oil on the dip stick, it didn't mix.
Any suggestions on where to start looking. Rebuilt oil pump and installed new rod and main bearings less then 300 hours on engine.