SOHC 1.9 1996, rebuild, no oil pressure

I have just finished rebuilding my daughters 1996 saturn SL1. Total rebuild, all standard sized parts, rebuild oil pump with new gears but not a new bypass valve. I have a pressure guage in one of the oil gallery plugs at the back of the engine to monitor oil pressure as it starts up. I packed the oil pump with petroleum jelly as instructed in manual to help the pump prime. I also prefilled the oil filter with oil.

To start the engine up I took all the plugs out and pulled the fuse on the injectors and cranked in a bit but no oil pressure. I then put the plugs in and activated the injectors and it started right up but after about 10 second I shut it down because I was not getting any oil pressure yet.

The question is how long does the engine have to run to prime and get pressure? I was told by my machinist that the oil valve (bypass or regulating valve?) in the oil pump never fails: leave it alone. Could this be the cause of the oil pressure problem?


I do have some experience rebuilding tractor engines, I'm on my third one now without any failures. But this is my first auto engine.

I had the same problem on a 95 but not on a rebuild, I did a timing chain replacement. Before I installed the timing chain cover (a second time), I squirted oil in each side of the oil pump, not too much or it will spill out when installing the cover. The oil pressure was a little slow in coming up, but it did.

You might try and squirt oil into the pump from the filter side, to assit in priming. I've never done it, but it may prevent you from pulling the timing chain cover.

I may have been reading wrong but did you rebuild the oil pump or did you buy a rebuilt oil pump, if you rebuilt it you may have not done it correctly, I am not saying anything about your mechanical ability, but Stuff happens. The oil pressure should have come up before you plugged the injectors back in, I would not recommend starting it anymore until you get the oil issue delt with or you may be looking at bearing failure to go along with it. the easiest route would be too replace the oil pump if you are not able to get the pump working, there are some things you don't want to skimp on, get a good quality oil pump, it is almost like the heart of your motor, it pumps the life fluid.