Fresh Rebuild - How Long to Get Oil Pressure?

Engine freshly rebuilt on 85 QV. Added nine quarts of oil and 16oz of Lucas break in additive. Poured as much oil as possible into the oil filter fitting. Plugs are out, coil wires disconnected, fuel pump fuses removed.

I cranked the engine in short 2-4 second spurts several times but the oil pressure light hasn't gone out yet and there are not any reading yet on the gauge.

How long should it take before I see oil pressure? Any other suggestions on "priming" it? Thanks

 

thanks classicalfas and mike996 - when I was cranking it for three seconds it felt like an eternity so 20 or 30 seconds will feel like a lifetime!!

Would there be any value in removing the oil filter right before cranking, adding more oil down the fitting, replacing the oil filter and trying again? Reason I am asking is that I filled the oil last weekend (and put a bunch down the oil filter fitting) but didn't try to crank it until last night.

Also, would there be any value in putting some light compressed air (like 10psi) in the oil filter fitting to get things moving?

 

Thanks Anthony - during the engine rebuild the oil pump was disassembled, and the gear lash was checked and was fine. Also will keep in mind your ideas about the gauge and/or bad sender

 

Last night I tried again to get oil pressure and turned the engine over for 25-30 seconds seven times and nothing. If the tach is accurate, the starter was spinning the engine at around 400 RPM.

I then removed the lower hose on the oil cooler and there was no oil. I'm not sure what to do next but have a sinking feeling it's going to involve a lot of disassembly.

One of the easier things to get at is the oil pressure valve, spring and shim so I'll open that up for any clues. Other than starting to try to access the oil pump, does anyone have other recommendations?

 

Thanks - please confirm you mean the bottom hose of the oil cooler which goes to the side of the engine block

Would it be better to take off the top hose of the oil cooler and fill that and let it run down into the bottom hose and into the block?

 

jdjagguy and smg2 — thank you for the details. Will try this method tomorrow and report back - Joe

 

Tried to get oil pressure again yesterday. First I filled the oil cooler from the top - it didn't take much. I also filled the top hose which goes back to the oil filter housing. I then removed the bottom hose on the oil cooler and confirmed oil was coming out of the bottom - it was. So I plugged the bottom of the oil filter temporarily and filled the bottom hose that goes into the block - again, it did not take much oil. Then went up top, removed the oil filter and filled there. I cranked the car for 30 seconds two times and the red light did not go out nor did I see any pressure building on the gauge. I looked in the oil fill opening on the rear cam cover and don't think I saw oil by the cams. I removed the oil pressure relief valve to the left of the harmonic balancer and there was not evidence that oil was there (other than the oil and assembly lube that was applied upon re-assembly). I then removed the upper and lower hoses again from the oil cooler and there was oil both on the oil cooler side and in the hoses going to the oil filter housing and the side of the block. I tried cranking again for 30 seconds two times and still no sign of oil pressure based on the light or gauge.

I have about nine quarts of Castrol 20/50 and 16oz of Lucas break in additive in the crankcase now - someone suggested draining that and starting over using thinner oil so I am going to try that with 5w-30. I also ordered an M18*1.5 to 1/8NPT adapter and an analog gauge.

Is the use of a thinner weight oil a possible solution to prime the oil pump? What other methods should I consider?

 

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smg2 - Thank you - I checked the gear lash on the pump gears and replaced the bearings and seals. Since this can't be accessed without removing the engine and separating the engine from the trans, what/how can I investigate at this point?

 

smg - below is a close up of the pump shaft which i think is showing a woodruff key at the 5 o'clock position but it's been a while and don't remember exactly.

Yes I installed a new gasket on the pump pickup to cover. Yes, the screen on the pickup was cleaned. The sump was also cleaned thoroughly....

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I'm pretty sure that when you assemble that timing cover to the block you can actually feel the gear mesh with the crank gear....

In any case, is there any way to service the oil pump without removing the engine and separating it from the trans, correct? For example, is it possible to remove the bottom studs and remove the oil pan and studs from the pickup and remove the front cover to access the oil pump?