Early 99' Powerstroke Fuel Leak

[99strokerPSD]

I started my truck this morning before I ate breakfast to let it warm up a little bit, and walked out to go to work and saw a puddle under the truck and a constant drip coming off the back of the engine. I had to go to work, but I did open the hood and check the valve behind the fuel filter. I got to work and asked permission to use the shop after work, and got to talking to a mechanic up here, and went to show him the leak. When I got out to the truck, I just turned the key on and pressurized the fuel system, and did not see the same leak as I did this morning. I will be jumping into this tonight after I get off work, and wanted to pick everyones brain as to where I should look. Thank you in advance for all the help.

[Banshee34]

Could that be the condensation off the compressor (or whatever that part may be) from running the defroster? I know mine has a leak whenever I'm running that or the air conditioning.

[sgleshot]

possibly the o-rings on the fuel dump valve? from sniffin around on here it seems like that could be possible.

[99strokerPSD]

Originally Posted by Banshee34

Could that be the condensation off the compressor (or whatever that part may be) from running the defroster? I know mine has a leak whenever I'm running that or the air conditioning.

Not the AC condensation, I backed the truck up and got out, it was pure Diesel Fuel!

[strokin_early_99]

O rings on the fuel drain valve on the back of the fuel bowl. #90 O ring from your local hardware store will get you up and running for about $1.

[powerplant]

Orings in the water dump valve when the temp change comes out side they shrink.Changed my valve last year you can replace the orings with out replaceing the valve trace the line down behind fuel filter from dump valve mine came down on passenger side of motor. to make sure thats what it is.

[jackpine savages]

My early 99 needed a fuel line replaced about 3 years ago. Pull the plastic cover off the top of the motor and check the one fuel line that runs across the top area. Mine had a friction wear hole from prior improper routing, etc...Re-built a fresh line at a friend's house in the boonies, where I was deer hunting, out of brake line with all the proper tools for making such a line. Has held up ever since.

[99strokerPSD]

Originally Posted by powerplant

Orings in the water dump valve when the temp change comes out side they shrink.Changed my valve last year you can replace the orings with out replaceing the valve trace the line down behind fuel filter from dump valve mine came down on passenger side of motor. to make sure thats what it is.

Thanks for the help guys, I can't wait to dig into this after I get off work, This is the first week of cooler temperature here in Missouri, that might just be it.

[99strokerPSD]

Originally Posted by strokin_early_99

O rings on the fuel drain valve on the back of the fuel bowl. #90 O ring from your local hardware store will get you up and running for about $1.

Will the standard #90 O-ring hold up to fuel, or will it desolve under a solvent?

[strokin_early_99]

I have had these O rings in my truck for the last 3 years. No leaks.