Help with fusible link blowing

[1FastCSX289]

So, my charger is deciding to be a real PITA. It blew a fusible link and I replaced it with in-line 30A fuse. It continues to blow. The thing that makes this tough is that its intermittent. I can replace the fuse and start and drive the car for a little while and then it will randomly die. It usually craps out on acceleration. Fuse blows, replace, rinse and repeat.

Hopefully, someone can tell me what might be on this circuit. Car is an 86 S/C. There is a large red wire that comes directly off the battery.....the one that has the connector in-line......it feeds the block where all the fusible links come together down by the drivers side strut tower. Well, the link that blew is the one that comes out of that junction block and feeds two red wires. Im thinking this is probably the main feed for the fuse box, which means that my problem could be anywhere. Anyone know for sure? Or.....does anyone know where i can find a diagram to show whats on that fusible link?

Thanks for your help!

Where can I get a diagram of what is on that fusible link?

[turbovanman²]

Get an old sealed beam headlight that has the low beam blown and hook the high beam side to the fusible link, it will glow bright if you have a dead short and will allow you to trace wiring, pull fuses until it goes out, when it goes out, you found your problem.

[quantum]

I had trouble once when I replaced a fuseable link with a regular fuse. It seems that fuseable links are "slow burn" where regular fuses are "fast burn". I ended up using a 30A breaker like this http://www.autozone.com/R,930208/sto...ductDetail.htm. It can handle a quick spike and auto resets if it gets "blown".

[Tony Hanna]

All my fuse link problems came from the 12v feed to the heater in the oxygen sensor. The wire had a bare spot in it and it would intermittently short against the engine and pop the fuse I'd replaced the blown link with.

[looneytuner]

You need a Max fuse and holder. As somebody said the fuseable links are slow burn.
Someone said they are at Walwart

[jonnyb]

does anyone know where i can find a diagram to show whats on that fusible link?

Thanks for your help!

Where can I get a diagram of what is on that fusible link?

There's a sticky at the top of this section with a link to a site that has a ton of wiring diagrams. Here's a link to the 86 L body page on that site: http://www.oldschoolhotrodder.com/mo...s&min=30&cid=3

Jon

[MiniMopar]

http://minimopar.knizefamily.net/electrical-links.html

[1FastCSX289]

Thanks for all the replies. Ill replace the link properly and then see if it continues to blow. If so, ill be back to figuring out whats causing it to go.

[JuXsA]

My money is on the heater wire for the o2 sensor

[jckrieger]

Did this ever get resolved? My 86 GLHS is doing the same thing... same fusible link, except I have 2 30A fuses in parallel (same as my 87 CSX). The fuses randomly blow on my GLHS, but I've run the same fuses in my CSX for years without issue. Let me know what you finally found, as I'm about to take the entire harness out of the car!

[1FastCSX289]

Did this ever get resolved? My 86 GLHS is doing the same thing... same fusible link, except I have 2 30A fuses in parallel (same as my 87 CSX). The fuses randomly blow on my GLHS, but I've run the same fuses in my CSX for years without issue. Let me know what you finally found, as I'm about to take the entire harness out of the car!

I put two fusible links in place of the fuses that I put in and havent had the problem since. Lots of miles on the car too. The fuses cant handle the quick voltage spikes that the fusible links can so they would blow randomly.

Why the initial fusible link blew, I dont know. But it hasnt resurfaced, and hopefully it wont.

[jckrieger]

Thanks for the update! I've wiggled my harness around, driven around the yard (nice and bumpy), and gone through the entire engine harness without finding any issues. The fast-blow fuses blew once, but now I can't get them to blow. I guess I'll find some slow-blow fuses/fusible links to throw in there and hope for the best. Definitely want something I can replace easily so I can carry a box of spares!

[looneytuner]

Thanks for the update! I've wiggled my harness around, driven around the yard (nice and bumpy), and gone through the entire engine harness without finding any issues. The fast-blow fuses blew once, but now I can't get them to blow. I guess I'll find some slow-blow fuses/fusible links to throw in there and hope for the best. Definitely want something I can replace easily so I can carry a box of spares!

And a pocket full is free with additional purchase at the yard.

[jckrieger]

And a pocket full is free with additional purchase at the yard.

Hell yes! Back in my regular yarding days I raided a few fuse blocks. I'd love to get a couple of those self-resetting circuit breakers...

[Clay]

Why the initial fusible link blew, I dont know. But it hasnt resurfaced, and hopefully it wont.

My bet would be on age, and repeated "voltage spikes/heat" cycling over time.

[jckrieger]

The insulation was definitely melted through on my link. The link blew on my CSX because a mouse chewed the insulation and the wire corroded. I'm guessing the hypalon links don't like exposure to oxygen much.

[t3rse]

best mod I made to my car was rewiring the whole damn thing....