Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of JUNE's Ride of the Month Challenge!

1 - 19 of 19 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter · #1 ·
Hey new here to the forum. I have a 360 swapped yj. While driving home today I noticed my voltage dropped to 12v. When i got it home i took a peek under the hood. Noticed a meted wire on a block that was on the fire wall. Any ideas what this is?
 

Attachments

·
Super Moderator
Joined
·
12,691 Posts
Welcome to the Forum Mrjr,

From what I can tell from your pic, that's a fusible link.
Other posters can suggest where to buy fusible links. Many folks that need to replace a fusible link, replace it with a spade fuse adapter. Then, solder and shrink tubing one end of the adapter onto the old wire after cutting away the burnt area.
I can't tell if you need a spade terminal or a ring terminal on the end that appears to go to your starter relay.

If you Google "fusible link" you might find the amperage that the link is designed to melt at. I think the amperage is determined by the wire size and is recognized by the color of the wire coating. You might even be able to buy fusible link wire at a site that describes what amps will cause the link to melt.

If you use the spade fuse adapter, you still need to use the same amperage fuse as the fusible link. Plus, something caused the link to melt. That needs to be discovered and repaired.

Good Luck, L.M.
 

·
Retired Moderator
Joined
·
100,641 Posts
:welcome: to the Forum..:wavey:
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #5 ·
Thanks for the info! I had no idea what that was. I found a site that had some info and it appears to be 12 guage. I'm going to replace it with fuses and it is saying to go with 160 amp (2 x 80) does anyone know if this is correct?

Welcome to the Forum Mrjr,

From what I can tell from your pic, that's a fusible link.
Other posters can suggest where to buy fusible links. Many folks that need to replace a fusible link, replace it with a spade fuse adapter. Then, solder and shrink tubing one end of the adapter onto the old wire after cutting away the burnt area.
I can't tell if you need a spade terminal or a ring terminal on the end that appears to go to your starter relay.

If you Google "fusible link" you might find the amperage that the link is designed to melt at. I think the amperage is determined by the wire size and is recognized by the color of the wire coating. You might even be able to buy fusible link wire at a site that describes what amps will cause the link to melt.

If you use the spade fuse adapter, you still need to use the same amperage fuse as the fusible link. Plus, something caused the link to melt. That needs to be discovered and repaired.

Good Luck, L.M.
 

·
Premium Member
'89 YJ 4.2 with MC-2150 Carb & HEI, 2-1/2" Ex. AX-15, NP231 SYE, Adams shafts, F&R ARB, 3
Joined
·
3,955 Posts
Dual fusible links are what was used on your stock wiring, You haven't filled out your signature yet, or told us what year and original equipment you had, but if you go into the dropbox link at the bottom of my signature you can find a FSM that will suit your year and scroll down to the wiring diagram section to find out what was specified on your original build, there is also a section in the FSM on how to repair a fusible link. Like LM said above, I'd be looking for the reason for the meltdown first before you do the repair
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #7 ·
Pretty sure I got the problem it was a ground wire. It's a 1990 Wrangler, seems like its 12 guage for the alternator link. I dont see your dropbox link maybe it's because I'm on a mobile phone


Dual fusible links are what was used on your stock wiring, You haven't filled out your signature yet, or told us what year and original equipment you had, but if you go into the dropbox link at the bottom of my signature you can find a FSM that will suit your year and scroll down to the wiring diagram section to find out what was specified on your original build, there is also a section in the FSM on how to repair a fusible link. Like LM said above, I'd be looking for the reason for the meltdown first before you do the repair
 

·
Premium Member
'89 YJ 4.2 with MC-2150 Carb & HEI, 2-1/2" Ex. AX-15, NP231 SYE, Adams shafts, F&R ARB, 3
Joined
·
3,955 Posts
Glad you have it narrowed down. In all things electrical we always start with the grounds, It seems to be a Jeep thing.

I think you have to take the it off the phone app and go to the regular website.

Good luck with the repair.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #9 ·
I got the fsm thank you! Its saying 14 guage is the a way to determine fuse size if I wanted to put this on a fuse? I noticed on mine there is 2 wires going into this link not one just curious if this differs from the fsm diagram.


Glad you have it narrowed down. In all things electrical we always start with the grounds, It seems to be a Jeep thing.

I think you have to take the it off the phone app and go to the regular website.

Good luck with the repair.
 

Attachments

·
Registered
Joined
·
15 Posts
Discussion Starter · #10 ·
Never mind the diagram show two 10 guage going to it. Now I just have to figure what size fuse.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #11 ·
Another question is it possible to run this to the battery directly instead of too the starter solenoid?
 

·
Premium Member
'89 YJ 4.2 with MC-2150 Carb & HEI, 2-1/2" Ex. AX-15, NP231 SYE, Adams shafts, F&R ARB, 3
Joined
·
3,955 Posts
I can't actually see what wire was actually toasted. I'm thinking no because you would be bypassing the solenoid relay, which handles the power on demand for the starter and bypassing would mean starter solenoid would be continuously energized. If you are handy with a soldering iron I would stay with the fusible link. You can replace the links with fuses, don't under size the wire, and don't oversize the fuse.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #13 ·
It is the one going to the alternator.


I can't actually see what wire was actually toasted. I'm thinking no because you would be bypassing the solenoid relay, which handles the power on demand for the starter and bypassing would mean starter solenoid would be continuously energized. If you are handy with a soldering iron I would stay with the fusible link. You can replace the links with fuses, don't under size the wire, and don't oversize the fuse.
 

·
Premium Member
'89 YJ 4.2 with MC-2150 Carb & HEI, 2-1/2" Ex. AX-15, NP231 SYE, Adams shafts, F&R ARB, 3
Joined
·
3,955 Posts
Another question is it possible to run this to the battery directly instead of too the starter solenoid?
I did not pull my loom apart to trace the wire back to the fusible link, but I believe that it is the larger wire size single brown/black link. If that's correct, as they all go to the same post as the battery cable I can't see why not.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #15 ·
Thanks for all the help, I soldered the 14 guage fusible link in. I cut about 6" as I dont know the original length. Took it on a long drive, pulled over a few times to check it. I noticed it was warm/hot but not enough to melt. Is this normal seeing as its protecting a larger guage wire? Drove it for around for a few hours.

Another question is it possible to run this to the battery directly instead of too the starter solenoid?
I did not pull my loom apart to trace the wire back to the fusible link, but I believe that it is the larger wire size single brown/black link. If that's correct, as they all go to the same post as the battery cable I can't see why not.
 

·
Premium Member
'89 YJ 4.2 with MC-2150 Carb & HEI, 2-1/2" Ex. AX-15, NP231 SYE, Adams shafts, F&R ARB, 3
Joined
·
3,955 Posts
Something made it blow to begin with. Me thinks if you got the ground wire nailed down you should be good. Yours was the first post I've seen about a fusible link so I would be watching it for a while. Next time I go for a longer trip than my usual drive to work I'll check mine to see if it gets warm.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #17 ·
So doing some more research, my alternator wire is 10 guage! It goes from the alternator to the starter solenoid. This isnt the factory one like the 4.2 it's a 135 amp. This seems way to small. I'm going to run a 4 guage wire from the alternator to the battery with a 150 amp fuse. I think this has been my issue the whole time.

Something made it blow to begin with. Me thinks if you got the ground wire nailed down you should be good. Yours was the first post I've seen about a fusible link so I would be watching it for a while. Next time I go for a longer trip than my usual drive to work I'll check mine to see if it gets warm.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #18 ·
Wrong size sorry 6 guage

So doing some more research, my alternator wire is 10 guage! It goes from the alternator to the starter solenoid. This isnt the factory one like the 4.2 it's a 135 amp. This seems way to small. I'm going to run a 4 guage wire from the alternator to the battery with a 150 amp fuse. I think this has been my issue the whole time.

Something made it blow to begin with. Me thinks if you got the ground wire nailed down you should be good. Yours was the first post I've seen about a fusible link so I would be watching it for a while. Next time I go for a longer trip than my usual drive to work I'll check mine to see if it gets warm.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #19 ·
Well I did end up going with 4 guage and a 150 amp mega fuse. Runs a whole lot better, this has an msd ignition, electric fan, electric fuel pump so I think that 10 guage wire was way to small.
 
1 - 19 of 19 Posts
Top