Just installed a new remanufactured 5.4l 3v in my 2004 f150. There weren't any instructions for priming the oil system before startup.

I did some googling and found a service bulletin that states to unplug the injectors and cops so no fuel or spark are in the cylinders and to turn the motor over via the key / starter for 3 x 15 second intervals. I would think that doing this would register some sort of oil pressure on the idiot gauge, but without having a real gauge, I get an uneasy feeling about this. Id like to be sure that oil is flowing somehow.

I watched a video by meling oil pumps about a forced priming system they offer for the modular motors, but it requires the use of the oil pressure sensing port - which the 5.4l doesn't have.

Anyone else have any ideas on priming for a first time startup on a fresh motor?
Thanks

 

Nothing needed other that making sure it's full of oil..just start her up!! If would make you feel better go by the SB you found, but it probably won't register on the idiot gauge. After starting and you don't see the needle (or light) go up within a few seconds, then shut it off. don't worry !!

 

I would just flip the fuel inertia switch and do the 3x15 second deal. I think priming is a good idea. If your worried about it pull the oil filter after doing the 3x15 deal and see if is full of oil.. probably just start unscrewing it if oil starts dripping out your good.

 

That's what I did. Tripped the inertia and did 3 turn overs for about 10 seconds or so. Flipped the switch back and fired it up. Mine was not a reman but had sat for many years.

 

I thought I read some place if you floor the gas pedal it won't start when cranking. Is that true?

 

Try it.

 

Whoa there bubba, sounds like a challenge. Guess I'll have to.:o

Couldn't stand it, I went out and tried it. Guess what?

IT WOULDN'T START! Nanner nanner!

 

Now you know....

 

Guess what??? I think your leg was being pulled... just for the fun of it, of course. The reason it won't start is because with no oil pressure and full throttle, the injectors are disabled. No need to trip inertia switch or pull injector plugs or anything else. I change the oil on my SIL's '07 F-150 as well as my own '04 F-150 and always do that after I've changed oil. If you don't, you have a rattle for about a second before it gets the oil, hold for about 4 seconds and let off the throttle without letting off the key and and no rattle at all because it's primed. With a new (or remanufactured) it will probably take a LITTLE priming, but I think even one 15 second starter run is excessive to get it primed. But 3X15 seconds is a little absurd. How many seconds do you think they give it at the end of the build line before they allow it to start??? 00000! By the time they do a burnout with it off the end of the line the oil probably isn't ALL the way circulated yet. I've worked with several guys over the years who at one time worked in US auto plants and you WOULDN'T BELIEVE some of the abuse your NEW vehicle sometimes has gone through after build before it ever left the plant lot.

DISCLAIMER: I DO NOT know if this works on prior to '04 (drive by wire) or not!!!

 

Code, mine's an 03 4.2 with a real throttle cable.

 

The modular rebuild manual I have said to fill the oil pump with assy lube prior to attaching the oil pickup tube. Thats what I did while building mine and it worked fine the first time I started it.

 

IF I were a betting man, my money would be that the THROTTLE cable engines MAY NOT disable the injectors, but that's ONLY a guess. It's really easy for them to do that on a "drive by wire" set-up, probably not as easy on conventional cable like yours.

 

I have even read that some use "white lube, light grease, and a variety of other lubes" in the oil pump upon engine assembly because they aid the "prime". The lubes easily and quickly are absorbed into the oil.

 

Code, mine is a throttle cable motor and it will not start with the pedal floored. But I don't know if that is because the injuctors are disabled or the spark is shut off. I think the PCM does shut off the injectors.

 

It does disable injectors on 97-03 mods/v6 when the pedal is pressed to the floor