Fusible Link?

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SASKCHEYENNE75

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Good afternoon,
I have no power to my headlight switch. I removed the switch and tested the contacts to make sure the switch is working properly and it is.
Next I checked for constant 12v power at the red wire in the headlight switch harness and there is none.
I disconnected the 3 wires from my starter and pulled them up to the top of the engine for easier inspection.

The thicker of the two smallest wires has this connector at the end. Is this the fusible link? I probably shouldn't have cut it off because now I have to replace it for sure. I just want to be sure I'm putting the same thing back on
 

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Jgonick

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yes- that's a fusible link.

Fusible links are usually 4 gauge sizes smaller than wire it is protecting.
You can buy them at an auto part store or make your own out of fusible wire-
 

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SASKCHEYENNE75

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1986 Chev K30
Now I'm left with these two wires that go to the starter along with the big battery cable. I'll replace the end of the smaller wire too likely. Does that need a fusible link too?
yes- that's a fusible link.

Fusible links are usually 4 gauge sizes smaller than wire it is protecting.
You can buy them at an auto part store or make your own out of fusible wire-
So both of these wires need a fusible link?
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Jgonick

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both red wires -all hooked to the same terminal- I would say yes. The diagram I attached is the typical wiring of an 86.
 

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75gmck25

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I used a TS-6 sending unit on my ‘75 and it is a pretty close match to proper temperature reading. The correct ‘75 vintage GM sending unit is only available as NOS, so it’s usually expensive. My gauge has no numbers, but fully warmed up to about 185 degrees it shows between 3/8 and 1/2 with the TS6. The TS6 also has the correct “button” connection for my original wiring.
 

BadBowtie

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Check the fuseable link up on the firewall too. Between the power brake booster and distributor.
 

Bextreme04

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Good afternoon,
I have no power to my headlight switch. I removed the switch and tested the contacts to make sure the switch is working properly and it is.
Next I checked for constant 12v power at the red wire in the headlight switch harness and there is none.
I disconnected the 3 wires from my starter and pulled them up to the top of the engine for easier inspection.

The thicker of the two smallest wires has this connector at the end. Is this the fusible link? I probably shouldn't have cut it off because now I have to replace it for sure. I just want to be sure I'm putting the same thing back on
If it is only the headlight switch... it isn't a fusible link problem. Did you check the headlight fuse in the fuse box?
 

SASKCHEYENNE75

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If it is only the headlight switch... it isn't a fusible link problem. Did you check the headlight fuse in the fuse box?
Yep the headlight switch was the first thing I checked and its operating as it should. As it turns out it was my fusible link near the starter. Replaced that and I'm back in business!
 

Bextreme04

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Yep the headlight switch was the first thing I checked and its operating as it should. As it turns out it was my fusible link near the starter. Replaced that and I'm back in business!
Interesting... you should have had a bunch of other inoperative stuff too then.
 

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