Just wondering if you have any ideas as to what the problem could be in our 1992 Dodge w250 with a rebuilt 5.9l 360 gas engine. Doesn't build any oil pressure when we crank it with plugs taken out and fuel pump disconnected. It's a rebuilt engine with the roller cam. Just wondering if you have any ideas on why it might not be building oil pressure. We tried cranking for 30 seconds twice and still nothing.
Was the oil pump primed?
Also, for future reference when posting a topic please use the title line for a short description of your vehicle issue, not the details which belong in the body of your post. Thank you.
@chucktobias I do apologize for that. I tried to change it, but couldn't figure out how to edit it. Anyways, the oil pump was not primed prior to installation. Would that make the difference in it not working as it should? Should we start it up and see what happens? Or drop the oil pan and prime the pump?
I do apologize for that. I tried to change it, but couldn't figure out how to edit it.
No problem, just making you aware of it. There is only a short editing window for regular members.
the oil pump was not primed prior to installation. Would that make the difference in it not working as it should?
Yes. Without priming the pump is sucking air until it manages to pull oil up out of the pan. Usually I prime them by packing with Vaseline. (That stuff dissolves harmlessly in the engine oil when the oil pump starts working.)
Should we start it up and see what happens?
I wouldn't. I know someone who did in a similar situation where a shop forgot to prime the oil pump. After driving a short time they wound up with oil visibly burning and a rod knock.
Or drop the oil pan and prime the pump?
You could do that. Or, if the oil pump is driven by the distributor shaft as in older Mopar V8s, you could use an oil pump priming shaft to spin the oil pump with an electric drill to build up pressure before starting the engine.