# TO-20 oil pressure



## Spikes (Sep 1, 2010)

Hi, I have a TO 20 that had a cracked block. I fixed the cracked block and changed the oil, hoping the oil pressure would come up with water-free oil..... It didn't.

There is basically no oil pressure at low to medium RPM and about 8 Lbs at higher RPM. This is according to the fairly new oil gauge that was installed by the previous owner during a (hillbilly) restoration. I have no idea how well the gauge works, it pulls from the starboard side of the engine just in front of the bellhousing mount.

The engine runs great after the carb rebuild and there is NO blow-by from the valve cover tube.... Just condensation drips from the old wet oil (I ran the engine for over an hour today to try to clear that out a bit.)

Any advice / tests I can try?

Thanks all!!!
Carl.

Edit:- There is a fair amount of upper engine noise, but I can't really tell if it's from the exhaust leaks on the carb side or the valves. It's no more noise than the 'parts' tractor I got from a friend... It has worn rings and lots of blow-by though.


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## rsmith335 (Jun 2, 2010)

I would try a low pressure test on the cooling- Radiator and see if the cooling side would hold any kind of pressure, if it dosen't you don't have the cracked block fixed or you have a gasket leaking somewhere. How did you fix the block?Good Luck


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## Spikes (Sep 1, 2010)

I used a product from CarGo called Seal-Up. It worked 100% like a charm! The radiator was draining into the oil pan and now the oil is clear and the radiator stays full. I followed the instructions to a tee though and over did each step.


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## Jerry/MT (Feb 11, 2010)

Spikes said:


> Hi, I have a TO 20 that had a cracked block. I fixed the cracked block and changed the oil, hoping the oil pressure would come up with water-free oil..... It didn't.
> 
> There is basically no oil pressure at low to medium RPM and about 8 Lbs at higher RPM. This is according to the fairly new oil gauge that was installed by the previous owner during a (hillbilly) restoration. I have no idea how well the gauge works, it pulls from the starboard side of the engine just in front of the bellhousing mount.
> 
> ...


Low oil presure on these old machines is not uncommon and the usual causes are a stuck open relief valve, a weak oil pump or worn bearings.

I would check the relief valve and me sure it's not stuck open and also make sure the oil pick up doesn't have any leaks. If if that isn't the problem, rebuild the oil pump. If that doesn't cure it, than the main bearing are probably worn. Once you drop the pan to work on the pump, you can Plastigage the bearings to check for wear.


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