Just installed a brand new 5.4 in my 09 superduty. Per manufacturer's instructions I disabled the ignition via unhooking the CKP and cranked the motor over in attempt to build up oil pressure. The instructions state to do this until pressure registers on the gauge inside the cab.


problem is, I've cranked and cranked it and am showing no pressure on the gauge inside. Can anyone confirm that the gauge will even register pressure prior to the motor running? I really don't want to try and get a manual gauge connected as this motor is a bear to work on as I'm sure lots of you know.


thoughts?

 

Update: removed oil pressure sensor and used a transfer pump to pump a few quarts of oil in there. Cranked it over a couple times, still not reading pressure on the gauge. Decided to fire it up for a second and the pressure immediately registered on the gauge.

It fired right up! No codes, no misfires. Small exhaust leak but I can fix that!!

I call bull**** on the whole using the starter to prime it method.

 

You likely just had a trapped air pocket, it's most definitely not bs. I've built many many engines over the course of my 40+ year career in this business and have always cranked the engine before starting it to get oil up to the top of the engine where it starves for oil the most on initial start.

 

More likely than not, the oil pump simply wasn't able to make enough pressure at cranking speed to trip the pressure switch. Usually around 4-6 psi is needed to do that.

Since it's fired up and running, it's now a moot point for this engine.

 

Pressure isn't the objective, presence of oil up top is.

 

Funtionally, absolutely. He was asking about the lack of the oil pressure indication while cranking. The "idiot" gauge requires a minimum pressure in order to register mid-scale.

 

Haven’t tried the 09, but my ‘10 f150 5.4 will register oil pressure by cranking over. It sat for quite awhile, so I just wanted to build some oil pressure before firing. Probly not relevant, but doesn’t hurt anything

Must’ve been an air pocket maybe, every engine with a healthy battery and starter should be able to build oil pressure by cranking I would think