black soot in fuel filter housing

[sam]

Hey guys, i have a 96 7.3 that the customer is staying it lack power. Went and drove it, seems fine, but kinda surges. Found a fuel leak at the lift pump and removed the fuel filter to see what it looked like. There is a black film on the walls of the housing. I looked thru the post to see if i could find where it has been talked about, but i am not having any luck. I do remember reading about it. I am leaning toward the injector orings but want to do more diag first. And i dont have a lot of experience with the 7.3, they seem to kick my butt from time to time... i guess i over think everything on them... but all help would be great... Thanks

[Keith Browning]

You stated that there is a film on the walls of the filter housing, how about the filter? More importantly how about the oil? Since a 1996 truck should have fuel return lines from the heads and back to the tank (if my memory serves me) leaking o-rings would allow engine oil to mix with fuel and in a 1996 truck the fuel in the tank and filter housing would be dark/black as well. Is the film oily or is it slimy and smell funky which would indicate a biological growth?

[Bruce Amacker]

Correct. If you would like some added reinforcement on the diag, disassemble the fuel pressure regulator and check for rubber chunkies inside, indicating the injector o-rings are bad.

 

http://www.forddoctorsdts.com/forums/ubbthreads.php?ubb=showflat&Number=17694#Post17694

 

Good Luck!