I just completed my install of a 2000 LS1 Corvette engine in my Silverado. I am running the Silverado, oil pan, oil pump pickup, oil pressure switch and harness. The PCM has been reprogrammed to suit the LS1 engine properties. I started it for the first time today. The dash gauge only showed max pressure of 20psi when throttled up and 10psi at ideal. These pressures didn’t make me feel too good, so I installed a mechanical gauge directly to the oil port. The gauge was reading twice the dash gauge, 40psi max and 20psi at ideal. If the oil pump was picking up air would that cause a low oil pressure? I am concern with the o-ring that was used to seal the pickup tube to the pump. It seemed to be tight and make a seal, but I am trying to come up with possible issues. Would a little bit of air effect the pressure that much? Does anyone have any suggestions? I have not weight out the idea that pump might be bad. Please any ideas?

Thanks

 

Does anyone want to give some input for low oil pressure?

 

You either dont have the O ring sealing correctly or your pump pickup is not installed all the way,

I'd tare it aprt and Re check those two things.

 

Definitely try replacing that o ring and that your pickup tube is seated all the way into the oil pump.

 

Thats the only thing i can think of, and that i have changed on the egine. There was some question about the pickup o-ring. How much suction does the pump create? Is the suction great enough to pull air cause a loss in pressure?

Thanks for your thoughts.

 

I agree, check the O-ring.

It's easier to suck air than a viscous fluid...

 

check o ring

 

Make sure that you have the red o-ring, not the blue one