Hi all.

my buddy has a f150 with a 5 ltr in it.
we were getting wood in the truck when it all of a sudden lost oil pressure and sounded like a diesel the way the lifters were knocking.
we shut it down and checked to make sure there was still oil in the engine. there was but it was over full and smelled like fuel.
when we started it back up there was no noise and oil pressure seemed fine, for about 5 min that is.all of a sudden we lost oil pressure on the guage and a few seconds after that the lifters started ticking again.
we shut it down and re started it and the oil pressure went back to normal, for about 5 min again.

then , bam , oil presure was gone and lifters were knocking.

every time we shut it off the oil pressure would return to normal for a while then suddenly drop to zero.

we got it home and he told me that the oil was changed but he forgot to buy a filter and that was quite a bit ago.
we put a new filter in it. the old one was really dirty,

no change except the guage read a little higher then usual and it took longer to loose pressure but it eventually did and started rattling.

now there was a lot of crap in the old filter and i was wondering if the fuel in the oil (still dont know were it came from, leaky lifter?) acted as a solvent and loosend all the sludge and crap up and then plugged up the filter and oil pick up.
anyways any input is awesome. thanks guys.

 

I'm going to say the same thing you already did about the pick up screen being clogged up.

Dirty leaky injectors could be why the oil smells like fuel.