gray fuel lines?
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Senior User
Joined: Dec 2003
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From: THE SOUTH
gray fuel lines?
new to diesels whats the deal with the gray fuel OEM lines. motor has about 95000 miles on it . its hard to start first thing or after a long time setting.
thanks for the help
Robbin
thanks for the help
Robbin
Post Fiend
Joined: Nov 2003
Posts: 21,285
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From: Nutter Fort, WV
The grey lines mean they are original.
There are O rings, two under each return tee and a rubber return line between the tee's that crack after years of hot fuel running through them.
The cracks may let fuel out or they may not.
But an air molecule is much smaller than a fuel molecule.
So when the engine is off, air leaks into the return lines and lets the fuel siphon back to the fuel tank.
The return line to the fuel filter lets the air into the filter.
No fuel, no start.
There are O rings, two under each return tee and a rubber return line between the tee's that crack after years of hot fuel running through them.
The cracks may let fuel out or they may not.
But an air molecule is much smaller than a fuel molecule.
So when the engine is off, air leaks into the return lines and lets the fuel siphon back to the fuel tank.
The return line to the fuel filter lets the air into the filter.
No fuel, no start.
Posting Guru
Joined: Oct 2005
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From: Powell River B.C.
Grey lines in this case means the original rubber return lines - when the engine first got built, the return lines got painted with everything else. Very seldom is there a problem with the steel lines as long as the vibration cluster clamps are all in place.
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also on my truck ive also noticed that the black sensor plug on the TOP (not the side screw in type) of the fuel filter mount seems to be leaking only when its running. is this part replaceable or do i need a whole new mount?? thanks N8
Elder User
Joined: Mar 2006
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From: North-Eastern, Ohio
I think you're talking about the "water in fuel" sensor. I don't know about the 7.3's, but on my 6.9 I can screw the sensor out (and now i have to replace it because my "hand tighting" is just too much for the plastic sensor) lol.
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From: missouri
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Originally Posted by F250FarmBoy
I think you're talking about the "water in fuel" sensor. I don't know about the 7.3's, but on my 6.9 I can screw the sensor out (and now i have to replace it because my "hand tighting" is just too much for the plastic sensor) lol.
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From: NC
Originally Posted by rockcrawlerdude
also on my truck ive also noticed that the black sensor plug on the TOP (not the side screw in type) of the fuel filter mount seems to be leaking only when its running. is this part replaceable or do i need a whole new mount?? thanks N8