Oil Pressure

[cassin12]

Hello,

I'm the (soon to be proud) new owner of a '87 F250 with a 6.9L Powerstroke. My question is concerning my oil pressure. When i start the engine, the oil pressure reads normal, but when the engine warms up, and i drive with a constant speed, i can literaly watch the oil needle drop down below the normal area. When driving on the highway in 5th gear (about 55-60 MPH, @ 2K RPM) the oil needle drops lower than the RED mark on the gage. I've just had the oil flushed and replaced with adequate oil, and the cooling system was also flushed out. I am wondering if anyone has any suggestions before I take it to FORD. The odometer says 34,000 but who knows how many hunderd thousand miles it has.

My reaction is to think crankshaft bearings worn, but this is my first diesel.

Thanks for any assistance.

F

[mschn99]

u will want to take a manual oil pressure reading to comfirm your suspitions...but if it truely loses oil pressure warm...then you are probably right

[cassin12]

so i am correct in my belief that oil pressure goes up with RPM? Haven't had a car with an oil gage in (wow) 9 years.

[cassin12]

Update:

I got my truck back from FORD, the mechanic found that the wire from the sending unit was being pinched, creating the affect on the gage and my paranoia. All is fine, and ford did thier normal inspection, so I am now a proud new owner of my first FORD.

F

[Yes]

I have the same oil pressure problem with mine. I do not think is a problem though. Maybe someone can clarify this for me. The 1987 6.9 uses piston skirt oilers that bleed off at low RPM. Does anyone know if this is fact or fiction? I called the mechanic that worked on the truck before I owned it.

My plans for this truck are WVO. Does anyone out there a 6.9 running on WVO. It already has two tanks. This should make it easy to do. Should the injectors be replaced for WVO?

[smokinnstrokin]

your 6.9 has nozzles that spray oil on the bottom of the pistons to keep them cool all the time. if i remember right, hot idle oil psi should be around 10 and wot should be 38-40.