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TR4/4A Restarting an engine - oil pressure problem

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T

TR4eh

Senior Member
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Hi,

This engine was last run 17 years ago. At that time, there were no issues with oil pressure - 50lbs cold, 20lbs hot, with 10W-40. The engine turns freely by hand now. I'm working to get oil pressure before I start it. I've tested the gauge. Turning the oil pump (CCW) by hand will fill the oil filter canister, verifying that the pump is picking up oil from the sump. But turning the oil pump faster with a drill does not produce pressure even after 30+ seconds.

Could the oil pressure relief valve be stuck, perhaps, and block oil flow up into the block? I see no pressure at the gauge and no oil at the rocker.

Any advice is greatly appreciated,

Cliff
 
Do you have the oil pump drive shaft in place, or something the same diameter? IIRC, the shaft needs to seal to the bushing, or oil just flows past it and out into the sump.

The rockers are not fed with oil directly from the pump, instead the rear cam bearing acts like a metering device to limit the flow. You may not get any flow at all with the cam not turning.

Could be the relief valve stuck open (or blocked that way by some sort of debris). That would also allow oil to flow back into the sump.
 
IYRC that would explain it, Randall. The screwdriver I'm using doesn't deal against the bushing. I don't want to take the distributor drive shaft apart but I should be able to find a suitable tool - it's 0.500 OD.

Thanks!

Cliff
 
Cliff ,with the oil pump primed, the only concern would be the cylinders being dry. The rest of the internals will have oil protecting them enough to start. Squirt some Marvel Mystery oil in the cylinders and crank it over with the starter ( until oil comes out the rocker arms if you like , but not necessary). An engine normally needs the reciprocating action to pump oil through it. I've revived many and would not hesitate to fire yours up - especially a TR engine.
 
IIRC, on mine I just pulled the ignition wire off the coil and cranked until I had 80 psi.
 
Thanks to all. After confirmed the pump was primed, by the screwdriver method, with 10 seconds of cranking I had 30lbs of pressure. Now to solve the absence of spark.
 
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