AZDIRT
Full Access Member
UPDATED W/ PICS! Very Low Oil Pressure after Changing Oil Cooler and Filter
Hey guys, My oil cooler sprung a pretty bad leak, so I pulled the entire cooler off of my 1992 7.3L Parts engine. I cleaned it up really good and replaced the O-Rings, and swapped out my leaky 1985 6.9L oil cooler for the 1992 cooler.
I changed the oil, switching from Rotella to 15W-40 Super Tech. I also replaced the stock filter with a Motorcraft filter for a Super Duty (holds an extra quart).
I did all of this, backed off the pump quite a bit (had it up 3 flats), and increased the timing a dime's width.
I then took the truck for a ride, with new oil cooler, oil change, and adjusted fuel and timing. The truck ran out very nice, but upon my return I noticed the oil pressure dropping almost to non-existence.
I then disconnected and removed the factory oil pressure sending unit and installed a mechanical gauge. Cold idle was 10-15, with up to 75psi showing at 3300 RPM. Hot, oil pressure drops to less than 5lbs at idle, getting up to 40-50psi at 3300 RPM.
Before changing the oil cooler, oil change and filter change, and adjusting fuel and timing, I have put about 20,000 miles on the engine and NEVER had the oil pressure drop at all.
Is it possible that the bypass valve in the rear header of the oil cooler is different from the 92 7.3L to the 85 6.9L? Should I try changing the rear header? Would this even matter considering how low my hot idle oil pressure is?
Has anyone ever had a problem going to the Super Duty oil filter? Would this even matter considering how low my hot idle oil pressure is?
I was just getting ready to sell truck (already bought another one), and now am worried I may have a bad engine...
Thanks
Hey guys, My oil cooler sprung a pretty bad leak, so I pulled the entire cooler off of my 1992 7.3L Parts engine. I cleaned it up really good and replaced the O-Rings, and swapped out my leaky 1985 6.9L oil cooler for the 1992 cooler.
I changed the oil, switching from Rotella to 15W-40 Super Tech. I also replaced the stock filter with a Motorcraft filter for a Super Duty (holds an extra quart).
I did all of this, backed off the pump quite a bit (had it up 3 flats), and increased the timing a dime's width.
I then took the truck for a ride, with new oil cooler, oil change, and adjusted fuel and timing. The truck ran out very nice, but upon my return I noticed the oil pressure dropping almost to non-existence.
I then disconnected and removed the factory oil pressure sending unit and installed a mechanical gauge. Cold idle was 10-15, with up to 75psi showing at 3300 RPM. Hot, oil pressure drops to less than 5lbs at idle, getting up to 40-50psi at 3300 RPM.
Before changing the oil cooler, oil change and filter change, and adjusting fuel and timing, I have put about 20,000 miles on the engine and NEVER had the oil pressure drop at all.
Is it possible that the bypass valve in the rear header of the oil cooler is different from the 92 7.3L to the 85 6.9L? Should I try changing the rear header? Would this even matter considering how low my hot idle oil pressure is?
Has anyone ever had a problem going to the Super Duty oil filter? Would this even matter considering how low my hot idle oil pressure is?
I was just getting ready to sell truck (already bought another one), and now am worried I may have a bad engine...
Thanks
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