[Vinnyjk123]

Just did a complete engine rebuild on the 4.7l. Tried to start her over today and found I need a fuel pump. Truck sat for 9 years so I can see why. Anyway, I rebuilt the engine top to bottom so I was looking at the oil pressure gauge religiously when I was cranking and wasn’t moving at all. Will the gauge show oil pressure when cranking, if so how much? Just has me worried. As far as I know my engine work is good... did not replace the engine oil pressure sensor at the filter, so I may change that also real quick. I can also try a manual gauge somewhere. Just want to know any insight in the meantime while I wait for my fuel pump to arrive. Anything would help. Thanks!

 

[radioactive]

That's a good question, I'm not sure if you can expect much oil pressure during cranking. RPM is lower than idle. Also if this is the first start attempt since rebuild you won't have much if any oil in the system, so it can take a while to build pressure, just like after an oil change.

I'd change out the fuel pump and go from there. If you don't develop oil pressure within 10 seconds of starting, that's when I'd be a little concerned - shut it down. Don't rev it or put a load on it.

 

[kiltkop]

Just rebuilt my 4.7L also. No you will not see oil pressure during cranking. Not enough pressure built up to register. When idling it will hover at the line above low and when you are driving it will hover at the line below high. No in-between.