1991 GMC topkick CAT 3116 no start

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by FOSSIL, Dec 3, 2023.

  1. FOSSIL

    FOSSIL Bobtail Member

    1
    0
    Dec 3, 2023
    0
    I have a 1991 GMC stake body truck that will not crank battery are fully charged .When ignition switch is turned to crank there is no power to the starter solenoid purple wire. Jumped the purple wire to B+ and the truck starts and runs. I Replaced the starter relay and still will not start I need to know where the neutral switch is and where the ground is for the starter relay . I am having a hard time getting a hold of a wiring diagram for this truck . Thank you for any help you can give me !
     
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. BoxCarKidd

    BoxCarKidd Road Train Member

    4,311
    6,249
    Aug 26, 2014
    0
    Those have been long gone from here but look for a relay to engauge the starter relay on the firewall somewhere.
    It maybe a smaller square black one close to where the back of the hood sets down.
     
  4. SmallPackage

    SmallPackage Road Train Member

    4,655
    14,051
    Dec 20, 2019
    Marion Texas
    0
    What @BoxCarKidd said. Our FL’s with 3126’s are same. If that remote relay/solenoid is bad it will not let power go down to starter solenoid. In a pinch You can jump terminals on it with screwdriver to get started most of time tho.
     
    BoxCarKidd Thanks this.
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.