Engine Harness?
 

I've been looking to locate a new engine harness for the 86 GMC C3500, but have found absolutely nothing available. They make them for up to 1981, but nothing after that...??? Am I missing something? I'm going to convert from the 6.2 to either a SB or BB...haven't figured that part out. If it comes down to it, I can splice and make it work, but figured a plug and play engine harness would be the way to go...any ideas?

Re: Engine Harness?
 

They still make the Packard 56 blade pins to re-pin the bulkhead connector. I have an 86 GMC that was 6.2 diesel originally, the previous owner blew it up and went with a 350. Needless to say the harness was totally butchered, so when I decided to drop in a new crate engine last fall I totally rebuilt the harness myself. It only cost me about $130 plus my time. I just took the old harness, peeled the tape off it and went wire by wire. Heads up the pink wire that went to your glow plugs, makes a damn fine HEI distributor power wire. other than that all the temp, oil, and alternator wires remain the same.

Re: Engine Harness?
 

M&H Electrical will be your go to for this.

Re: Engine Harness?
 

Here is a wiring diagram book from Classic Parts.

Link: https://www.classicparts.com/1986-Wi...tinfo/52-993P/









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