Just drained my oil to replace my oil pump. I get no oil pressure and was wondering if I'd be able to do a compression test without oil and an operable pump or do I have to wait til I replace pump and then do compression test?

 

I would want oil in mine if I was you. You will have to cycle the engine multiple times to do it. You would likely be ok but why risk it.

 

How do you know the oil pump is inop, giving you no oil pressure?

Have you tried using a direct reading oil pressure gauge in the place of the oil pressure sensor to see if the oil pressure sensor is defective?

Why do you want to jump to a compression check when you have an oil pressure problem to deal with?

 

I drove about 1.5 miles with no oil pressure and wanted to check piston ring damage before I dropped pan and putting it back on only to find out rings are bad and having to drop pan again for repair

 

Have you confirmed you hd no oil pressure using a direct reading gauge?

When you were driving it that 1.5 miles, was the engine making knocking noises?

 

Did you or didn't you already drop the oil pan and pull the pump???
Like mentioned before. Did you verify that you actually have no oil pressure with a mechanical pressure gauge?

 

Yes there was knocking noise. And I was just thinking it could be something to do real quick to determine if there's any discrepancy from me driving without oil pressure.

 

No I haven't dropped pan or pump

 

BEFORE you do that pull the cps/distributor and inspect the pump drive. It may be broken. That would explain the loss of pressure, the noise could be coming from a broken pump drive. I have seen them snap in two.

 

Rog

 

If it's not broken wouldn't it cavitate since there's no fluid?

 

What's wrong with this picture?