Wiring issue!

[jwill945]

1976 GMC Jimmy
Intermittent no crank/no start problem. I found 2 bad grounds (from battery to alternator bracket was pulled out of battery terminal and engine to cab was off). I repaired the one to alternator bracket and reconnected the one from engine to cab. Still have issues.
My next thought was ignition switch. So pulled gauge cluster to make sure it wasn’t lose or rod twisted up. PO put in Equus gauges and they were silicones in place with wires duct taped together. I pulled all out except Speedo/odometer and oil pressure gauge. Still nothing.
Then I went back to battery. Has good grounds per the multimeter, but wire to starter was twisted at starter. With key on, I could move wire and hear it arc. I removed that but can’t find any replacements. I see it should have a fusible link, but have no idea where or how to make one.
Anyone have a good source or tips on how to make this wire?


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[dvdswan]

Is the truck a manual? Could be the clutch interlock going bad. Also, look at the ignition switch on the steering column under the dash.

 

[dsteelejr]

I see it should have a fusible link, but have no idea where or how to make one. Anyone have a good source or tips on how to make this wire?

You can buy fusible link from the car parts stores. Some carry it, some don't. You can also get it from amazon:

Fusible Link Wire 14 AWG Gauge Universal Black 10 FT Spool Coil - USA Made

Fusible Link Wire 16 AWG Gauge Universal Black 10 FT Spool Coil - USA Made

Fusible link should be four AWG sizes smaller than the wire you need to protect. For example, if you have a 10 AWG wire, protect it with a 14 AWG fusible link or 12 AWG wire you would use a 16 AWG fusible link and so on. I make my fusible links three inches long. To do it properly you'll need butt connectors and a ring terminal connector to hook it to the positive post on the starter. You'll also need wire, wire strippers, crimper, and heat shrink.

I have a bunch of wire, fusible link, and connectors, plus all the tools, left over from recently rewiring my 1980 K25. I could make you a wire and mail it to you if you are having trouble with it.

 

[AuroraGirl]

Is the truck a manual? Could be the clutch interlock going bad. Also, look at the ignition switch on the steering column under the dash.

this

I kicked my clutch safety switch wiring once and it unplugged. I am not sure if it was hanging low from my Gpa in the past or if time and placement of my foot made for a match but it would be a good check if its a manual truck

 

[jwill945]

Is the truck a manual? Could be the clutch interlock going bad. Also, look at the ignition switch on the steering column under the dash.

Automatic. I looked at ignition switch, seemed ok but I couldn’t verify with the bad starter wire. Hoping that replacement takes care of the no crank.


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[jwill945]

You can buy fusible link from the car parts stores. Some carry it, some don't. You can also get it from amazon:

Fusible Link Wire 14 AWG Gauge Universal Black 10 FT Spool Coil - USA Made

Fusible Link Wire 16 AWG Gauge Universal Black 10 FT Spool Coil - USA Made

Fusible link should be four AWG sizes smaller than the wire you need to protect. For example, if you have a 10 AWG wire, protect it with a 14 AWG fusible link or 12 AWG wire you would use a 16 AWG fusible link and so on. I make my fusible links three inches long. To do it properly you'll need butt connectors and a ring terminal connector to hook it to the positive post on the starter. You'll also need wire, wire strippers, crimper, and heat shrink.

I have a bunch of wire, fusible link, and connectors, plus all the tools, left over from recently rewiring my 1980 K25. I could make you a wire and mail it to you if you are having trouble with it.

So for a 10 gauge wire, I’d splice in a small section of 14 gauge right before the starter?


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[jwill945]

You can buy fusible link from the car parts stores. Some carry it, some don't. You can also get it from amazon:

Fusible Link Wire 14 AWG Gauge Universal Black 10 FT Spool Coil - USA Made

Fusible Link Wire 16 AWG Gauge Universal Black 10 FT Spool Coil - USA Made

Fusible link should be four AWG sizes smaller than the wire you need to protect. For example, if you have a 10 AWG wire, protect it with a 14 AWG fusible link or 12 AWG wire you would use a 16 AWG fusible link and so on. I make my fusible links three inches long. To do it properly you'll need butt connectors and a ring terminal connector to hook it to the positive post on the starter. You'll also need wire, wire strippers, crimper, and heat shrink.

I have a bunch of wire, fusible link, and connectors, plus all the tools, left over from recently rewiring my 1980 K25. I could make you a wire and mail it to you if you are having trouble with it.

I’ll be picking your brain as I dig deeper into the instrument cluster!!


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[dsteelejr]

So for a 10 gauge wire, I’d splice in a small section of 14 gauge right before the starter?

I would have the 14 AWG fusible link coming right off the starter. That way if the wire shorts anywhere the whole wire is protected from right off the starter post. That’s how I did mine.

This pic is one of the wires I made for the primary power off the starter. It was a little too short, so I added a little more 10 AWG to lengthen it. Afterwards I decided to scrap it and just make a whole new wire because I wanted the fusible link right at the starter. Just showing it here as an example. The black portion is the same fusible link I got from Amazon and I linked to in my first post.

Be sure to use fusible link and not just wire. The difference is fusible link has thicker, heat resistant insulation to contain the heat and not catch fire if the fusible link blows from a short.

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[jwill945]

I would have the 14 AWG fusible link coming right off the starter. That way if the wire shorts anywhere the whole wire is protected from right off the starter post. That’s how I did mine.

This pic is one of the wires I made for the primary power off the starter. It was a little too short, so I added a little more 10 AWG to lengthen it. Afterwards I decided to scrap it and just make a whole new wire because I wanted the fusible link right at the starter. Just showing it here as an example. The black portion is the same fusible link I got from Amazon and I linked to in my first post.

Be sure to use fusible link and not just wire. The difference is fusible link has thicker, heat resistant insulation to contain the heat and not catch fire if the fusible link blows from a short.

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Gotcha! Thanks a ton.
I’ll be picking your brain as I dig deeper into the instrument cluster!!


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[75gmck25]

Look for one of these at the parts store. It’s sized to fuse a 10 gauge wire. https://shop.advanceautoparts.com/p...QWg2cIU8a8HlUezP6l4aAsKUEALw_wcB&gclsrc=aw.ds

Most parts used to stock these, and the package label often said “GM fusible link.”

 

[MikeB]

Automatic. I looked at ignition switch, seemed ok but I couldn’t verify with the bad starter wire. Hoping that replacement takes care of the no crank.


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No cranking or intermittent cranking could be the neutral safety switch, which allows the ignition switch "start" terminal (purple wire) to connect to starter solenoid only when column shifter is in Park or Neutral.

 

[jwill945]

No cranking or intermittent cranking could be the neutral safety switch, which allows the ignition switch "start" terminal (purple wire) to connect to starter solenoid only when column shifter is in Park or Neutral.

Didn’t have time after work today to get new battery cable for starter, but will update as soon as I can. Gotta go to a few different parts stores to gather supplies at lunch tmr.


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[jwill945]

I would have the 14 AWG fusible link coming right off the starter. That way if the wire shorts anywhere the whole wire is protected from right off the starter post. That’s how I did mine.

This pic is one of the wires I made for the primary power off the starter. It was a little too short, so I added a little more 10 AWG to lengthen it. Afterwards I decided to scrap it and just make a whole new wire because I wanted the fusible link right at the starter. Just showing it here as an example. The black portion is the same fusible link I got from Amazon and I linked to in my first post.

Be sure to use fusible link and not just wire. The difference is fusible link has thicker, heat resistant insulation to contain the heat and not catch fire if the fusible link blows from a short.

You must be registered for see images attach

You must be registered for see images attach

You called it! Burnt up fusible link at the starter. I think it actually got worn on the metal tube the wires were running through, but got that all replaced today. Pulled the starter to get to everything, forgot how heavy those bad boys are!


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[jwill945]

No cranking or intermittent cranking could be the neutral safety switch, which allows the ignition switch "start" terminal (purple wire) to connect to starter solenoid only when column shifter is in Park or Neutral.

This is the next task now that I have verified I have good power to starter, good wires from switch back to starter, and good grounds. What am I looking for when I drop the steering column?


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[Raider L]

@jwill945,

Yeah, that's what I was thinking was the neutral safety switch due to having that problem here recently. And after replacing everything, like what you've been doing whether good or bad the neutral safety switch was the last thing I could think of, I'd done everything else, and I'll be darn that's what it was. Well, I won't be having starting problems for a very long time since everything that has anything to do with starting is new...now! See, I should have known it wasn't any of the other stuff when I put a remote starter switch on the starter and it wouldn't crank then. That would have told me it may have been something out of alignment. Anyway, good that you found it before you spent money on new starters and stuff.