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Cummins M11 trouble

Discussion in 'Trucks' started by barklee, Jul 1, 2010.

  1. barklee

    barklee Senior Member

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    ohio
    I just bought a Kenworth t800 with a Cummins M11 330hp. I bought it knowing that the ECU was bad. So i took it off and had it rebuilt. The truck is doing the same thing that is was doing before hand. It will run off either and it appears like it is pumping fuel. Strange thing is the filter is only about half full (it has a steel spin on filter) after running the truck on either. There is no hand pump on the motor so i would take off the filter and fill it up, crank it and check the filter which is half full at that point. The injectors are under the cover so i cant crack them to eliminate that. However when you crank it and crack the line at the injection pump it has good fuel coming out??? So i guess that tells me there is something electrical stopping the fuel or there is a check valve stuck somewhere?? I have no experience with this motor so any guess would be helpfull
    Thanks!!!
     
  2. muzy

    muzy Well-Known Member

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    Next time you have the filter off. Take a look at the O-rings might be missing one or have one to many. You might want to get some gauges on there, just becuse there is fule comming may be low preasure. And if you would like this truck to live, leave the either alone, unless it is -23 C over there. Could be alot of things. muzy
     
  3. John C.

    John C. Senior Member

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    As I recall there is supposed to be an O ring at the base of the stud that the filter screws on to. If none there that could be your problem.

    Good Luck!
     
  4. ontrac

    ontrac Well-Known Member

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    Oklahoma
    I am assuming the truck will not start, there is a fuse at the battery box area or along the frame by the starter, check it. Sounds simple but I have had two trucks not start over this in the last month. fuse blowed no start unless on either. fuel seamed to be patial at fuel filter but return line pumped well. Let us know what it takes.
     
  5. barklee

    barklee Senior Member

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    I had a buddy come look at it and plug it into the diagnostic. He said that the computer is not communicating with his computer. He thinks it is something stupid like a fuse or broken wire, but wasnt able to locate it. I guess he said Kenworth and Peterbilt are notorious for rotting wire connections which i have a few of those. I am i the process of getting the wire diagrams from Kenworth to have a better idea how to track it down. I had a pickup do something similar a while ago and it was a broken ground wire so i am hoping its something easy like that.
     
  6. ontrac

    ontrac Well-Known Member

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    That is what the fuse I am talking about does. Sterling right at battery box, International two wires come frome battery box inside frame rail next to starter fuse holder. volvo at battery box. it is the only fuse at the box. check it out.
     
  7. ontrac

    ontrac Well-Known Member

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    Did you Fix it yet?
     
  8. Muffler Bearing

    Muffler Bearing Senior Member

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    Occupation:
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    Colorful Colorado
    make sure you are getting power to the fuel shut off solenoid on the back of the pump. is the red engine light staying on when you turn the key on?
     
  9. barklee

    barklee Senior Member

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    ohio
    Finally got this truck running today! We took the computer out of another truck and put it in.... still didnt work. Then after going through alot of the wiring noticed that there was a spade terminal rotted off! The wire altogether was in bad shape so we replaced the whole thing and it fired right up. Turns out that Kenworths are notorious for the fuse panels getting wet and rotting the terminals out.
    On a not so good note, we reinstalled my computer and the truck would not run. I just had the thing rebuilt so i am sending it back to be looked at. :Banghead I am already guessing that this is going to be a problem! They are going to say that it works fine when i know for a fact it doesnt!
    Wish Me Luck!!!!!