Shopping for Fusible Links

[DIY 1985]

Can someone point me to a vendor who is selling amperage-rated fusible links for 12V systems that I can use to refresh my '85 wiring harness with?  Thanks in advance.

[Charlie69]

Take a picture of your fusible link as there are many different combinations.  I might have an extra used one to get you by.

Fusible link facts

 

 

A) common wire sizes
B ) their name as a given gauge (AWG=American Wire Gauge)
C)permissible current when used in the engine compartment (176degrees and
D) other areas.

A B C D
0.3 AWG22 - 5A
0.5 AWG20 7A 13A
0.85 AWG18 9A 17A
1.25 AWG16 12A 22A
2.0 AWG14 16A 30A
3.0 AWG12 21A 40A
5.0 AWG10 31A 54A

Mitsubishi fusible links by color and size. Size shown is millimeters squared.
Color and Wire Size
Brown 0.3
Green 0.5
Red 0.85
*Black 1.00 (diesel glow plug circuit)
Black 1.25

Fusible links are to be two wire sizes smaller than the wire they protect would would mean the following:
A Brown fusible link is used to protect an 18ga wire.
A Green fusible link is used to protect a 16ga wire.
A Red fusible link is used to protect a 14ga wire.
A Black fusible link is used to protect a 12ga wire.
Mitsubishi uses these colors, others may NOT so you'll have to look at the wire size to be certain.

Fusing current is in older manuals but that depends on how long that high current is present
.3mm is 100amps
.5mm is 100amps
.85mm is 150amps, 15 sec or less
*1.00mm is 160amps, 30 sec or less, or 270amps if 5 sec. of less
1.25mm is 190amps, 15 sec or less

Continuous permissible current if:
temp. is 176degrees or less
.85mm is 34amps
1.25mm is 40amps
temp. is 212 or less
*1.00mm, is 26amps

*is the glow plug circuit of the diesel engine

If you want to replace fuse links then get a DSM maxi fuse holder, those are attached to the battery post but why? You can have these just the same and sometimes those maxi fuses get stuck in the holder. Why replace with a fuse and a different holder its still there and fuse links last a very long time and can take power surges. You can buy fuse links from many places or just buy the wire and make your own.

Edited June 15, 2020 by Charlie69

[DIY 1985]

Two greens, two reds, and a black.  One green is rigged.  I'd rather not deal with crimping in the OEM connectors.

 

[Charlie69]

I will look in the morning.  If I have one it will be plug and OEM used.

[KELMO]

Seems like the hardbody had the same fuse link...maybe.

[Charlie69]

Here is what I have.

 

 

 

 

 

PM me if you are interested.

[Joecar]

On 6/20/2020 at 3:04 PM, Charlie69 said:

Here is what I have.

 

 

 

 

 

PM me if you are interested.

Hello is this still avalible

 

[720_Jeff]

These are NLA long ago 😞

[Joecar]

20 hours ago, 720_Jeff said:

These are NLA long ago 😞

Is there a way to fix or bypass them?

[Seven Two Oh No]

@JoecarYou can fix this like any other wire. Take the fusible link harness off the truck and figure out which wire is bad using a circuit tester. Once you find the bad wire, check the color against the table Charlie posted here (or Mike posted in your other thread on this topic) to figure out what amperage replacement wire you need, then buy a roll on amazon, O'Reilly, etc. (again, check your other thread). Next, pull the bad wire(s) out of the harness - they have blade connectors on both ends that you can pull out of the plastic pieces. Note that the battery side will likely have 2 or more wires on one connector. Finally, cut the new fusible link to length, solder/crimp on new end connectors, and put it all back together. Otherwise, you can take Draker's advice on the other thread and bypass the bad fusible link with a new slow blow fuse circuit.

[Stoffregen Motorsports]

I use fusible link wire, which I buy in bulk. Pico is one brand and you can get it just about anywhere. https://www.summitracing.com/search/part-type/fusible-links/product-line/pico-fusible-link-wires

 

I also ditch the factory connectors and either install high quality ring terminals or Deutsch connectors. Be careful though. Many connectors are rated at much lower amps than a main power wire delivers (like the alternator power wire). To clean things up a bit, I use small gauge battery terminals and group three or four fusible inks in one connection, crimped together in one terminal. They can go either straight to the battery, or if you want an even cleaner installation, make a short main battery cable that runs to a "power post" and use that as your power distribution center.

 

For fuse link sizing, the fuse link wire needs to be four number sizes smaller than the wire it protects, so if you're protecting a 10ga wire, a 14ga fuse link is used. Length is important too. I generally cut the fuse links to three or four inches long.

 

In this pic, you can see the power post and the three fuse links crimped together into one terminal.

 

[720_Jeff]

I can say, had an old fusible link laying around, one wire is shredded.  Was wanting to rehab the whole thing, but can't get the connectors out of the Black connector that connects to the battery.  Not sure exactly how the crimp-on connector is being held in by the black housing.

 

So, it can be a little bit of a challenge.  

 

Edited April 15, 2022 by 720_Jeff

[720_Jeff]

I'll add, these can be found at the junkyard occasionally.  Usually, they are completely missing.  Not sure if they are removed when the junkyard is removing the battery, or previous owners just removed them.

Either way, they can be found at the junkyard, just not all of the time.

 

[Sephakrid]

I got around to cleaning the fusible link wires on my truck so I could actually read the markings. They seem to follow the Mitsubishi color code that you listed. My 1984 truck has black, green and orange/brown wires.

Black - 1.25

Green - 0.5

Orange/brown - 0.3

 

 

 

 

 

 

 

Edited January 20 by Sephakrid
New image links

[datzenmike]

'Orange' isn't used but the California emissions uses two Brown, two Green and one Black. They are really Brown.

[NC85ST]

What system does the red, orange, brown (whatever color you want to call it) fusible link protect? One of those two fusible links burned through on my truck and I don’t find any system that’s affected.

(Don’t mean to hijack this thread)

 

[datzenmike]

In the event of a catastrophic accident it protects the power wire to the headlight fuses, power wire to the fuses for things not switched off by the ignition such as horns, brake lights, 4 way, clock etc. and the power wire to the ignition which switches power to the fuses for wipers, radio, heater etc. Once to the fuse box all wiring is fuse protected but from the battery to the fuse box they are not. In an accident they could easily be pinched and grounded. They would heat up like a toaster element and start a fire.

 

A fusible link can sustain a dead short for several seconds but will eventually melt. They have a very special Hypalon plastic outer insulation that is heat resistant and won't catch fire. Never replace with ordinary plastic coated wiring and never use a higher amp rating fusible link.

[Thomas Perkins]

This is mine on my 85.I have a new spare.Not parting with it.

[Thomas Perkins]

My Head lights quit working once and it was the fusible link.I think it was the  red one.It melted the  plastic on the yellow connector that is use to connect  both wires.All I did was replace the yellow connector.All my wires that connect to the fusible link that has male connectors all dry rotted so I replaced them with these.

[NC85ST]

I understand what a fusible link does, but what I don’t understand is what system those red, orange, brown fusible links protect. One of those two links is burned through right now, but everything still seems to work.