78 chevy k20 fusible link size help

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I am replacing the starter on my truck. There are two wires that come down from a wiring harness and connect to the starter. They both have fusible links on them but they have been replaced at some point and the fusible links that are on there are really janky and look too big. I can’t read anything off the old wiring. I was wondering if anyone knows the size of the two fusible links so i can replace them. Currently there are some exposed wire nut bolt things holding the fusible links on.
 

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I might consider replacing each with a 40amp fuse and going from there, so hard to figure out the rating if that fusible link?
 
Below is a page out of the GM service manual for my Camaro which describes fusible links in general terms. You will have to locate a specific manual for your truck that shows the wiring diagrams to determine the specific gauge of the fusible link required to protect the circuit in question.



I'm not an auto electrician but I did find one caution of replacing fusible links with fuses:
 
The Link with 2 circuits splitting off.....
*1 circuit goes the the Voltage Regulator, The other feeds the Fuse Block.
The Link with a single circuit feeds the Junction Block up on the Firewall.

Those Links, Because where they're placed cause a lot of grief & fires.

There isn't a reason not to convert to Mega Fuses. Two 40 amp fuses would be perfect.

I use Fuse Holder GM part# 19116352, It's only $17. Unfortunately it comes with fuse way larger than you need so you'll need to buy 2 40 amp Mega Fuses.....Littelfuse or Eaton/Bussmann ONLY!

Use a 4 gauge wire to power the Fuse Holder, Mounting the fuse holder close to the battery is ideal because the 4 gauge wire will not be fused.

The 2 circuits that feed the Fuse Block run behind the engine, Don't be surprised if you need to cut these 2 in the middle somewhere to find "good" copper to solder to, Even if you butt splice....You need clean copper for a good connection.

Swap the 125 amp fuse to the top, Then install the 2 40 amp fuse in the bottom 2 slots.

Use the picture/diagram below to upgrade your Body/Charging circuits.

D1dp4uE.png

0wQDyFR.png







 
The Link with 2 circuits splitting off.....
*1 circuit goes the the Voltage Regulator, The other feeds the Fuse Block.
The Link with a single circuit feeds the Junction Block up on the Firewall.

Those Links, Because where they're placed cause a lot of grief & fires.

There isn't a reason not to convert to Mega Fuses. Two 40 amp fuses would be perfect.

I use Fuse Holder GM part# 19116352, It's only $17. Unfortunately it comes with fuse way larger than you need so you'll need to buy 2 40 amp Mega Fuses.....Littelfuse or Eaton/Bussmann ONLY!

Use a 4 gauge wire to power the Fuse Holder, Mounting the fuse holder close to the battery is ideal because the 4 gauge wire will not be fused.

The 2 circuits that feed the Fuse Block run behind the engine, Don't be surprised if you need to cut these 2 in the middle somewhere to find "good" copper to solder to, Even if you butt splice....You need clean copper for a good connection.

Swap the 125 amp fuse to the top, Then install the 2 40 amp fuse in the bottom 2 slots.

Use the picture/diagram below to upgrade your Body/Charging circuits.

D1dp4uE.png

0wQDyFR.png







Thanks for the idea but i went with replacing the fusible link.
 
I use the factory service manual and reading various forum posts and determined i needed a 14ga fusible link. Which makes sense because the power wire from the cab looks like 10ga. Also fixed the janky solenoid power wire from ignition switch.
 

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