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Diesel Fuel Problems 6.9L Ford 1984


A 1984 Ford Truck equipped with a IH 6.9L diesel engine is smoking very badly. Fuel problems for sure. This video is a diagnostic step-by-step elimination of causes resulting in the conclusion that the injector pump is failing.

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25 Responses to “Diesel Fuel Problems 6.9L Ford 1984”

  1. crazymoviedude1 says:

    I figured out why? you had this problem in the first place. . . Bad luck. (see black cat at 1:19)

  2. maxhauler says:

    Thanks for the great video, man! I always appreciate when there is more technical info and a look at the important parts and steps. This video helped me get a few ideas when I was diagnosing my bad fuel/lift pump in my 1988 F250 with the 7. 3. ? I ended up bypassing the mechanical lift pump on the engine block with a little electric pump activated by a relay, sitting under the hood. Temporary setup until I purchase a proper performance electric pump + filter system. Got me back on the road though.

  3. RANDYSTREX500 says:

    fuel return line is? plugged. . . . . . . . . . . . . .

  4. estalt957 says:

    Diesel finally? check up.

  5. DrMcelroy says:

    dunn98632. . . Hopefully if it runs out of anything, it runs out of diesel. . . Not gas. Haha. Anyway. Put diesel in the tank, bairly crack an injector? line at the injector and crank the engine. When is starts you can tighten the line. If its a manual tranny, you can also crack a line and roll it downhill or have someone pull it while its in 2nd or 3rd gear if it dont start by cranking the engine.

  6. DrMcelroy says:

    I didnt? watch the whole vid but right after seeing it run i said ” yep, needs a new pump “. I bought a remanufactured pump when mine went bad, it was $450 with the core charge. When they go bad they begin sucking air which makes a rough idle and white smoke.

  7. wood0702 says:

    check the fuel lines under the fuel/water? seperater, they tend to be pinched. I the same problem with my 84 6. 9.

  8. luke9john says:

    i never thought that this would? fix my truck. thanks

  9. guppyelf says:

    @dunn98632 easy, fill up the fuel filter , pop the #8 injector line, just loose not off, , ? you may need to crank some but do not crank for more than 30 seconds , let starter and battery cables cool off after each try ,,

  10. dunn98632 says:

    what is the proccess to get a diesel start after running it out of gas?

  11. dunn98632 says:

    and fill your filer with diesel too helps on starting back up? as well.

  12. MrJumpcamp says:

    check ball is on the front elbow therre actually. But you got air iin your? lines. find the leak. problem solved.

  13. Jacksonkellyfreak says:

    sounds like hes sucking air into? a line and losing prime

  14. elcuatedejosefina says:

    Tnak’s for sharing your experince? with us.
    I got the same exactly ford and its working awesome but it will help me for the future just in case. ,

  15. r22accipiter says:

    Where did? you send the injector pump for rebuild? I probably need to do the same.

  16. tpvalley says:

    how would a failing injection pump allow debris into the system? the fuel filter stops that.
    why would a blocked feed line cause smoke, wouldnt it just reduce fuelling or is it cavitation causing the pump to run retarded?
    I had same problem on different type of car, similar pump design (lucas,cav, stanadyne), seems they only run properly at idle if u advance the pump when they’re failing? but they then missfire at high load.

  17. n6ugy says:

    We cleaned the check valve on Ed’s 84, but there was only a film of varnish, no chunks. Cleaned it out with carb cleaner and blew air thru it. He made it? all the way home without it dying, but it’s too soon to tell. I hope to get an update from him later today. Dennis

  18. n6ugy says:

    Is the crap in the valve, dropping the fuel pressure to the injectors, making them dribble instead of spray, causing? a rich condition ? Dennis

  19. n6ugy says:

    My friend Ed has a beautiful 84, and it started dieing at idle on a regular basis. He said he replaced both filters, and one hose. I sent your video to him and told him to clean that valve for GP. Have you got any idea’s about his dieing problem ? He said when it dies, it has to crank? for about 20 seconds before it restarts, and sometimes it idles fine. Dennis

  20. bigbraunboy says:

    yea how how to? get the injection pump rebuilt?

  21. Raiden7800 says:

    How? much for the rebuild?

  22. tom58c says:

    Well a gasket isnt to bad, so thats good but not good, lol. I think a new pump is like 500-600$. So hopfuly? you wont be spending that much.

    But your welcome. I like vids like this.

  23. richkrichk5 says:

    Tom – Thanks for your comment. Turns out that there is a gasket inside the injector pump that gives out and degrades. The evidence is in? the check valve. The IP needs to be rebuilt. I have sent mine in to be rebuilt and am waiting now to get it back. Thanks

  24. tom58c says:

    Looking forward to the? next vid to. :)

  25. tom58c says:

    Awsome video. ? I have heard many people talk about this, but never show it. I really want to buy this 85 6. 9 f250, it runs great. This video helps me see what to look for or keep a look at. Thanks, you have no Idea how much it helps.

    Saved in favorites, and 5*.

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