Fusible Links

[Lynx]

Im replacing a fusable link down by the starter with a Fuse holder. Wondering what Amprage fuse to stick in there'?

[GMC Jim]

a fusible link is a short piece of wire that is 4 gauges smaller than the wire it protects......so you can make your own " fuse".... with the smaller gauge wire !

[86-C10-V6]

I think fuse link wire has a special resistance value to create heat and cause it to burn at a controlled amperage, it also has special insulation that won't catch fire.

If you want to use a fuse, it should be sized for the size wire in the circuit; 12 guage would be 20 amp fuse, 14 Guage:15 amp fuse, and 16 guage:10 amp fuse.

Also be aware that fuse link wire is very slow to burn, you may have problems with blowing fuses with regular fusing.
Fuse link wire is easy to find, just prefab with quick connectors so you can replace easily.

[NeCrOmAnCeR]

Also remenber that a fuse holder will corrode or become dirty over time and the added resistance will cause extra heat build up. I would replace the fuseable link with another to avoid that problem.

[piecesparts]

The fuseable link wire does have a resistance rating and if you put in a fuse holder you may have just passed up the real reason for that being installed in the first place. You will see mechanics measuring the length of the wire and replacing it with the right size and length.

[GMC Jim]

Per 1971 Chev Truck Chassis Service Manual :-- Page 6Y-1; Quote "Protection for the battery charging circuit (10 gauge wire ) is provided by a pigtail lead which is a fusible link off the battery positive cable ( 14 gauge wire ) "

Page 12-1; Quote " All wiring systems not protected by fuses incorporate a fusible link which provides increased overload protection. The starting motor circuit is the exception. "

Page 12-1; Quote " When replacing wires, it is important that the correct size be used. Never replace a wire with one of a smaller size. Fusible links in the Chevrolet wiring are four gauges smaller than the cable it is designed to protect. The links are marked on the insulation with wire gauge size because of the heavy insulation whick makes the link appear a heavier gauge than it actually is."

There appears to be nothing "special " about fusible links other than the link is "four gauges smaller than the cable it is designed to protect ". Solid wire, rather than stranded wire is recomended for constructing links.

[GMC Jim]

Fusible links are used in a variety of applications. I installed a hydraulic lift gate on a truck equiped with a utility bed.... This was powered by a 12 volt motor similar to a stater motor which turned a hydraulic pump.... Used 4 gauge heavy duty wire cable from the truck battery to an enclosure in the utility box. Installed a short link of 10 gauge wire near the motor for protection. This was much simpler than using a cartridge fuse ... Would have required a fuse of about 75-100 amps.. as the current draw with a loaded tail gate was substantial.

[Lynx]

Yeah im just going to go ahead and order some cause i cant get any in town lol.

[86-C10-V6]

The special insulation that makes the wire appear larger should be a clue that the wire is special.
You can buy fuse link wire in rolls of about 4 feet long and cut to the length you need, it will be marked "fuse link" on the insulation.
I have not purchased any for quite some time but I am pretty sure I saw some in Autozone and PEP boys recently.
All the fuse link wire I have seen is stranded, not solid.
Also the wire is almost impossible to solder, something about the coating on the wire, plan on using crimp connections to join to the circuit wiring.

[Izzy]

You can get them at Autozone and O'reillys for $2 each, just got some recently.

[GMC Jim]

Checking with a wiring specialist at a GM dealer; I was told the same information as contained in the GM Service manuals> Nothing really " special " about this wire other than ; as stated in the manuals " fusible links are 4 gauges smaller than the wire it protects"....The heavy insulation is used over the link for purposes of easy location on the link in the event the link has failed. Also the heavy insulation serves to keep the wire from separting in the region of the fusible link.....

I don't mean to argue with anyone about all this; but I am a firm beleiver inthe data contained in the manuals published by the manufacture of any product.

[86-C10-V6]

I don't mean to be confrontational either, but I don't see any eletrical design engineers running around in any of the GM delearships I have been in.
The fuse link wire is designed to be a "SAFE" device that will not have the insulation burn into and cause a fire.
Think about it,
if you use regular wire, it can burn into and come in contact with the frame and continue to burn until it reaches the "non fuse link" wire and then the circuit is no longer protected.
I don't believe in wasting money, but I think safety is the most important aspect of any repair.
In my opinion, useing the wrong wire is unsafe and should not be advocated.
Please lets be safe.