L1801DT Low Oil Pressure (Not cam shaft plug)

[CasualNerd]

I have had the low oil pressure issue many people have had with this late 70's machine, and assumed from seeing other posts it probably needed the cam shaft plug repair. I took the whole front of the tractor off, removed the sump and oil pickup which was clean and clear, removed the timing cover only to find the cam shaft was already plugged with a little bit of steel stamped in.

The symptoms were intermittent oil light on at low revs once warm, flashing at up to 2000 revs, usually stops above 2000 revs.

I'm at a loss now because after all this work I'm none the wiser as to the cause of the low oil pressure and I really don't want to start putting things back together until I have some idea of what else might be the issue.

Any suggestions before I just throw thicker oil in and send it ? ?

 

[85Hokie]

Might need to check the same plug on the rear of the camshaft.

Or you could have some excessive bearing/journal wear - how many hours on this engine?

 

[D2Cat]

Probably install a mechanical gauge to see if you actually need to do anything! Oil pressure light will come on a 7 PSI presumably.

 

[Motion]

I'm not familiar with that engine. Did you put a pressure gauge on the oil circuit to confirm pressure. Is the oil sender unit good? connections? Does the oil pump have its own relief valve? Just my .02

 

[GeoHorn]

Yep..... What kind and weight of oil?... What actual pressure?..... How many hours?

High hours = worn Main bearings. Solution: Start using heavier-weight oil. I ran my 9N Ford on straight SAE 50 oil for 15 years. Sure was cheaper than another rebuild.

 

[CasualNerd]

IIRC it has 1600 hours on it, what do we consider high hours ?

I have a new gasket set and some heavy duty diesel 15w-40 oil ready to reassemble, is that going to be heavy enough or what's suggested for heavier oil ?

I will look into the oil pump and if there's a relief valve, I haven't looked into that.

I'll try and borrow an oil pressure gauge but that's not much help till I reassemble it and I don't want to start this whole process again. I guess being that everything looks in decent condition I don't think there's much else to be done.

 

[CasualNerd]

UPDATE....

I'm an idiot. I pulled the camshaft, had a repaired plug at the back too.

Got the machine back together - full bottom gasket set, new head gasket, lots of swearing to get the front axle back on and the 4wd driveshaft back in place

Borrowed an oil pressure gauge and it has constant 60-65 psi oil pressure.

It was the sensor failing when warm I think, a new one is ordered.

 

[GeoHorn]

Thanks for the update!

Be Happy! Bottom line: Ya done good!

 

[lmichael]

Yep on an electric sender always verify with a real gauge