I have an Oliver 1365 that suddenly lost all oil pressure while building a brush pile. When I started it that morning, the pressure was normal- about 40 lbs. While pushing brush, I heard a slight "clink" from somewhere up front, but dismissed it a loader noise. A few minutes later, I could smell hot oil. Checked my gauges and found no oil pressure. Shut it off, checked the oil level and found it normal. Looked for any outward signs of problems and found nothing. Restarted the engine just long enough to verify the total loss of pressure, then shut it down. When I towed it into the shop and dropped the oil pan, I found an 8mm bolt about 1 1/2" long lying in the bottom of the pan. It was bent at a 90 degree angle and part of the head was missing on one side. My conclusion was that it must belong in a hole that goes back into an oil galley, and it being out is allowing the oil to "free flow" without building any pressure. I've removed and inspected the oil pump and found nothing wrong . I've pulled the vibration damper down from the engine and found nothing wrong. So far, I can't find a hole where it belongs.
From lying underneath the engine looking up, I can see that the main oil galley appears to run right beside the camshaft. My only remaining theory is that this bolt may belong in the cam retainer plate and it's mounting hole is drilled back into the the oil galley.
Does anyone have any experience with one of these Fiat engines? Or does anyone have a engine out of a tractor that they could look at and see where this bolt could have possibly come from?
In order for me to get into the timing cover on this one is major surgery.
Any ideas or suggestions would be greatly appreciated.