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1997 Genie z45-22 w/ deutz engine starts then dies

Discussion in 'Forklifts/Telehandlers' started by Jpcady, Apr 18, 2017.

  1. Jpcady

    Jpcady Member

    Joined:
    Sep 19, 2016
    Messages:
    6
    Location:
    Westford, VT
    So, I had a thread going last fall about my Genie lift, then it got snowy and wintry, and I didn't use the machine much, and didn't want to work on it in the freezing VT winter and never really got to the bottom of my problem. Now that it's spring I need to get it up and running.

    Last fall I was having a problem where the machine would start and run, but after a few seconds, would not go to high idle when the function switch was pressed. I thought was the high idle solenoid, then I thought it might be the ecm, or a relay. after a bunch of testing, I replaced the relays in the ground box, I bought a new ECM and installed, and disconnected the leads to the idle solenoid, and didn't solve the problem. At the time, I had a jumper from the key power, to the fuel solenoid because the solenoid wouldn't open. I realized that this was maybe clouding the problem, since the machine was still running.

    First off, I took the jumper wire off of the fuel solenoid and hooked it back to the original wiring. I don't remember why I originally jumpered it, but I think that the fuel solenoid wouldn't shut off. Anyway, now that the fuel solenoid is hooked up right, the engine does NOT stay running. The symptoms are:

    Engine start, run for 5-10 seconds, dies. The ecm lights go out except for #7.

    When I RE-hook my fuel solenoid jumper I notice 2 things-

    1) the back studs on the alternator (not the battery wire, but the other terminals) drop to 0v, even though the engine is running. Is this normal? I would think that they would still produce power. Or maybe this is the problem? The alternator is new last year.

    2) the controls still work. The function enable switch still works, and the machine booms slowly because the engine is running at low idle.

    So, I'm not sure where to look now. Maybe the alternator? Maybe something I'm overlooking?

    Help,

    Jake
     
  2. skata

    skata Well-Known Member

    Joined:
    May 10, 2007
    Messages:
    210
    Location:
    midwest
    it seems the ecm is looking for a signal to see if engine is running, otherwise it shuts off the fuel. it may be that the alternator is the signal the ecm is looking for. not sure.
     
  3. 92U 3406

    92U 3406 Well-Known Member

    Joined:
    Jan 3, 2017
    Messages:
    70
    Occupation:
    Field Service Tech
    Location:
    Oilsands
    What exactly is this jumper wire hooked to?
     
  4. Jpcady

    Jpcady Member

    Joined:
    Sep 19, 2016
    Messages:
    6
    Location:
    Westford, VT
    So, the machine is fixed. For future searches, here is what was wrong and how I fixed it.

    First off, I had the fuel solenoid jumpered from the power wire from the emergency stop switch (constant power when switch is on) because I was having a problem with the solenoid not opening the fuel rail. This allowed the diesel engine to keep running even when the ecm was kicking off, and lead me down the wrong path in trying to diagnosing the problem.

    To eliminate wiring problems with the engine harness, I used jumper wires from the ground control box wiring block, to each of the connections on the engine harness. (Oil temp, oil press, tach, ignition, fuel solenoid) the tach and ignition wires attach to the back of the alternator.

    The jumper wires made the engine run. So I unplugged the sensors one at a time to test, and neither one killed the engine. It turns out, the alternator wires were faulty. I think the ignition wire is the "excite" wire to turn the alternator on, and it wasn't turning it on, so the ecm was kicking power off because it wasn't seeing rpms from the engine.

    I pulled new alternator wires through the loom, and eliminated the harness plug on the engine in favor of direct wiring each sensor. Cleaned it all up, and it seems to be running like a champ.

    Thank you guys for the help. I needed the insight about the ecm not seeing something and shutting down. I hired a tech from my local genie rental shop to come out for onsite service yesterday, and he checked all of the same things I did, and was stumped. He was pretty sure it was the ecm not sensing something too, but didn't fix anything. That visit cost me $350, but I saved another head scratching $$$ visit by testing it out this morning.