Oil pressure issues IH350U

[Mtjohnso]

Put new main, rod and cam bearings. Did not turn crank. Did use plastic gage to check clearance and in tolerance
When starting engine at idle 15 pounds, at high rpm 30 pounds initially then back to 15 pounds.
Has original oil pump. Bottom plate of oil pump has been sanded flat.
New oil gauge.
Checked for oil coming up through rocker arms at idle and no oil. Evidence of oil at higher rpm.
How to troubleshoot?
There is a 1/4 inch nipple on dip stick side of engine. Could test a different oil gauge there.
Could I use this port and pump oil through the engine to check for oil flow. Concerned about blockage in oil system.
How to determine if it is the oil pump?
How would you troubleshoot.

 

[Mrfred54]

What about the oil pressure regulator spring and spool inside the oil pump?? On these old engines, when I rebuild them I usually throw a couple of small washers in the spool to beef up the spring pressure. All oil gallies were cleaned out??

 

[Duner Wi]

How does oil pressure now compare with old oil pressure?

 

[gmcdeadhead]

make sure you have the correct shim/gasket for the bottom of that pump, I rebuild my pump on my IH504 , and now I have 45-50lbs of HOT oil pressure at operating temp , before I only had 15 lbs at operating temp

 

[used red MN]

Was this a running tractor when you got it? Did this tractor always have low oil pressure? You have a lot of threads about oil pressure in this tractor. For the most part Farmall H and Ms and there ancestors (this is an ancestor of an H) usually have no problem carrying good oil pressure. I take it that at operating temperature while at an idle the oil pressure shows zero, is this correct? The oil filter on these tractors is a bypass type and I believe it relies on a small restriction about a 1/16” diameter in the center tube that the filter slides on to meter oil. You might check to see if someone has tampered with this. Otherwise it may come down to finding or building some type of system capable of pumping oil into the engine. Then pull the pan and connect that and see if you can see where the oil is escaping. Probably have to build something out of an old oil pump to do this. They want quite a bit of money for purpose build primers that use a container capable of being pressurized with air.

 

[D Slater]

Put new main, rod and cam bearings. Did not turn crank. Did use plastic gage to check clearance and in tolerance
When starting engine at idle 15 pounds, at high rpm 30 pounds initially then back to 15 pounds.
Has original oil pump. Bottom plate of oil pump has been sanded flat.
New oil gauge.
Checked for oil coming up through rocker arms at idle and no oil. Evidence of oil at higher rpm.
How to troubleshoot?
There is a 1/4 inch nipple on dip stick side of engine. Could test a different oil gauge there.
Could I use this port and pump oil through the engine to check for oil flow. Concerned about blockage in oil system.
How to determine if it is the oil pump?
How would you troubleshoot.

First thought that comes to mind is center cam bearing lined up correct? If it is and no oil pressure the oil may not make it anyway. Thinking oil passage from front to rear of block has 1/8 pipe threads on right side of block. They would be at same level as line to oil pressure gauge fitting with center one the easiest to get at. Clearance of oil pump teeth to body of pump at ends and backlash of gears maters also but doesn't usually result in no pressure. Oil pump drive shaft had wear problems at one time and better shafts used to replace. Pumped oil travels up between pump body and shaft to oil gallery. Any loss from shaft or pump body in block will lower oil pressure. Probably not this if you had pump apart. But if a utility has the oil pan bent up bad or replaced check for a crack along body. Found this before because lower to ground.