tonylittell

94 f-150 with a 5.0 .....let it idle for 30+ min and its fine. drive it and after about 10-15 min i lose oil pressure and it starts ticking......let it cool off to where the engine is almost completely cool and i got oil pressure again..... any ideas?


thanks for the help!

tony

wde3477

Hmm - well, the ticking would just about eliminate an instrumentation problem as far as a gauge inaccuracy.

Just to get a clearer picture - what type and weight of oil do you use, what brand oil filter, how many miles on the engine, any unusual past history with the engine?

Couple of wingnut thoughts - the bypass spring is sticking or weak, the oil filter has collapsed, the oil pickup screen is plugged - all very unusual events.

tonylittell

just got the truck a couple months ago, so i dont know history. put new fl1a motorcraft filter and castrol 10w-40 high mileage oil when i bought it. oil is clean as can be on the dip stick and right on as far as level goes.....it definately not a gauge issue cause after running for about 5 minutes with it showing zero pressure it ticks right good.....

aliens8mycow

Mine's doing almost the exact same thing, except it ticks all the time. Does yours show pressure until it's idling? Mine shows about dead center on the guage until it's been driven 15-20 minutes, then if you're sitting at idle the pressure goes down. The needle even jumps along with the tick.

Mine is going to a shop this week for someone more skilled than I am to figure it out. If I find anything out, I'll definitely let you know.

tonylittell

similar, except mine will idle and i can even put it in gear with emergency brake on and it has pressure. After i drive it about 10-15 min and the water temp gauge gets just over 1/2 way to the hot side it loses pressure all together no matter if it is moving or at idle.... once the engine sits about 2-3 hours it gets oil pressure agian

andyman7931

I'd put a mechanical oil pressure gauge on there to see what the pressure is. If the crank bearings are worn, the oil will not build pressure when warm.

DixieDarkhorse

i agree with putting a manual gauge on it, and oil does thin out as it gets warmer

tonylittell

im not sure what putting a manual gauge on it would do? i know for a fact its losing pressure. after it shows 0 oil pressure the engine starts ticking right loud, i would think its apparent that it has no oil pressure. am i missing something?

sorry, dont mean to sound like an *** or anything, i just dont understand what a gauge will do

can you explain?

DixieDarkhorse

i think everyone in the forum agrees the factory gauge is pretty unreliable, thats why but i understand your frustration. with a mechanical gauge you'd be able to see exactly what the pressures are and when. how many miles are on this engine? did this start recently or has it always been like this?

tonylittell

i bought the truck about 2 months ago with 140k on it and just put it on the road last week. i understand the gauge isnt accurate in alot of cases. i think you are missing part of my post though. when the gauge shows zero pressure my motor starts to knock. that is why i ask why it matters how accurate my gauge is. when it shows oil pressure it runs great. when it doesnt the motor starts ticking very loudly. in my eyes it tells me it is accurate enough to say there is an actual oil pressure problem and not a gauge issue... unless im missing something.... again i am not trying to sound like an ***. i just dont see the sense in spending 60 dollars or so to run a mechanicle gauge to have it tell me something i am almost certain of