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Fuel Injection Pump Wiring Issues?

Discussion in '6.9L IH & 7.3L IDI Diesels' started by BryantMarwitz, Jan 14, 2020.

  1. BryantMarwitz

    BryantMarwitz Registered User

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    Hello all, I should have posted last night but I was hoping to figure the issue out without asking. Just dropped my rebuilt engine in the truck and I have been working like crazy to get everything finished on it because school starts in a few days and I don't have a truck.

    Anyways the just of the issues is. I have fuel at the IP pump plenty of it. The shut off solenoid to the IP pump works, I can hear it click when you turn the key to the run position. The metering valve is free, made sure of that last night. I've gotten the to back injectors wet with diesel, not a ton of it just a little bit. However, no matter how much we crank we don't get any fuel to the other injectors. So we continued troubleshooting. I checked the wiring and the wire going to the shutoff solenoid gets 12.5 volts with the key in the run position but when the key is in the starting position the wire that goes to the shutoff solenoid goes dead. I've traced the wires back to the relay on the fender but nothing seems ary. Is power supposed to continue to the shutoff solenoid while the key is in the start position?

    I just can't seem to figure this one out any help would be much appreciated
     
  2. SLC97SR5

    SLC97SR5 Full Access Member

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    If the rear injectors are getting fuel, the fuel solenoid isn't really a suspect anymore.

    Fuel filter full?

    Try cracking a few of the easy to access lines coming from the rear of the IP and verify fuel is coming out there.

    If it is, tighten them back up, put a charger or a set of jumper cables on the batteries and continue to crank.

    You can also remove the main return line from the rear of the head before it empties to the tank and make sure it is flowing fuel freely and not kinked during install.
     
  3. BryantMarwitz

    BryantMarwitz Registered User

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    Fuel filter is full, lines aren't kinked and only the back two injectors got fuel. As I mentioned the hot lead that goes to the glow plug relay goes cold when the key is placed in the start position. This lead runs back to the IP and is what control the shutoff solenoid. From what I understand this solenoid has to be kept hot to keep the engine running so if the lead is going cold when you turn the key then the IP can't send any fuel to the injector lines. I'm just confirming that this is the case.
     
  4. SLC97SR5

    SLC97SR5 Full Access Member

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    Sorry, I read past that.

    To eliminate any wiring/key issues, run a jumper straight from the battery to the IP solenoid and try again. This will ensure the solenoid remains open and energized.
     
    SlippyRider, dgr and Thewespaul like this.

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