Major Wiring Issue 84 Sierra 2500

Discussion in 'Classic GM' started by IsThrowingTools, Oct 4, 2016.

  1. IsThrowingTools

    IsThrowingTools New Member

    Posts:
    3
    Likes Received:
    0
    Joined:
    Oct 4, 2016
    General rundown: Bought a mostly stock 84 Sierra 2500 GAS, it's had a 350 crate motor dropped in. The wiring harness on the front end has been completely half assed, too many fuses connecting short wires, and grounds where they shouldn't be. It's a MESS. When I hit the ignition, it will crank, run for 10 seconds max, blow a fuse and die. As far as I can tell, this particular fuse is Only to feed power from the Ignition to the Starter. But it kills the truck when the fuse pops...
    I can barely make heads or tails of the harness in it's current state, so I'm hoping to start from scratch from the firewall Forward (under the hood Only, dash wiring is fine) I need a clear picture of a Correctly wired harness or the Original wiring diagram to fix this crap...help...
     
  2. JC00GMT800

    JC00GMT800 New Member

    Age:
    32
    Posts:
    3
    Likes Received:
    0
    Joined:
    Oct 5, 2016
    Google searches will definitely help with your wiring diagrams.

    Sent from my SAMSUNG-SM-G900A using Tapatalk
     
  3. IsThrowingTools

    IsThrowingTools New Member

    Posts:
    3
    Likes Received:
    0
    Joined:
    Oct 4, 2016
    Tried Google already for well over an hour, it won't pull up the correct harness for the Gas 2500, only the Diesel. If there weren't so many differences I would try to use that for a basis to go off of, but the harnesses are completely different. Also tried looking under a couple other similar vehicles and same problem, there's just too many differences that I know aren't supposed to go on this truck. Ended up running a hot wire straight through the system to get it running for now, but I'd really like to redo the Whole front end harness so I can avoid future issues with it. Haven't found anywhere that will sell it as a whole like they do on four wheelers either. If anybody could just post a picture of the Correct harness layout that would be absolutely fantastic
     
  4. daved931

    daved931 I have t-rex arms

    Posts:
    107
    Likes Received:
    41
    Joined:
    Jan 21, 2015
    Location:
    Maine
    If you buy a Haynes or a Chiltons manual, it should come with some wiring diagrams.
     
  5. kids-at-711

    kids-at-711 Resident Bath Salt Consultant

    Posts:
    2,446
    Likes Received:
    666
    Joined:
    Oct 28, 2012
    Location:
    Over There------>
    IIRC Painless makes a complete replacement harness for that truck. Its a bit pricey tho.
     
  6. daved931

    daved931 I have t-rex arms

    Posts:
    107
    Likes Received:
    41
    Joined:
    Jan 21, 2015
    Location:
    Maine
    At my last job we had a 1989 V30 and I bought the painless harness for it. I think it was $700.
     

Share This Page