Fusible Link

[Gerald Morris]

If you've got the time and patience, ditch the bulkhead altogether and use a terminal bar or even some straight insulated spade connectors. Be sure your wires have enough slack if you do. BTW, I have a #16 awg fusible link I cribbed from a 68 at the bulkhead from my fave junkyard. IT is a full 6" long. If yours is short, it likely BURNED SHORT. I know they can because the first #12 link I made at my alternator, also 6", burned down to about 1" when a wiper motor lead I'd missed in my post-alternator disaster re-wire effort grounded while I was climbing a 50 degree driveway west of town. So don't be afraid to give some length to your new link. Odds are, it originally HAD it.

 

[rexus31]

As Big_John pointed out, do the job correctly so you don't have any issues in the future and so you don't burn the car to the ground.

 

[rexus31]

This is what your fusible link should look like, minus the parts tag. Notice there are two ends that are crimped on. One goes in the bulkhead and one is clipped to the other wire.

What's the p/n on that? He may be able to source an NOS unit.

 

[Big_John]

What's the p/n on that? He may be able to source an NOS unit.

That was on Ebay. I just did a quick search to find a pic.

 

[furyfever]

Rexus...I was an Electro-Mechanical Technician for 30+ years at Xerox Corp. This experience certainly does not make me an expert. And I never will be an expert at anything, so...when I'm at a loss at how to fix something, I ask a lot of questions to make sure I fix it properly. Taking it to a repair shop doesn't insure that it will be fixed properly and the cost is usually insane, so I won't be taking my Fury to a shop to get this fixed. Plus...I do believe it's within my capabilities. Thanks...I appreciate your input and the photos of your fusible link but it's obviously a different setup. Now...if someone made the type that's in my 68 Fury...and posted each step, that would be the ticket!

Big John...thanks a million for helping me. You have made it crystal clear. Seeing those terminals helps me immensely. I'll be buying that terminal set you posted on e-Bay, so I can fix this the right way. Sure would be nice to find an original pigtail like in the first photo you posted, but the Dorman #85627 looks like the best I can do as I've done a bit of research on this now. I had Advance Auto order me one last night and these terminals from E-bay will be what I need to finish the job. Now...to figure out how to easily get the old terminals out of the connectors...At least I know where to squeeze/push now after seeing the terminals.

Thanks again...Bob

 

[furyfever]

Got both terminals out with no problem...thanks again John. The fact that you knew what type terminals were in there and...that you included that link to the e-Bay auction was key. Both ends are the same (males). I thought the bottom one would be a female. Wire is 5" long...about 6" total with terminals. Hmmm. If I remember right, the Dorman fusible link is about 7".

 

[Big_John]

I thought it may be a male on one end and a female on the other. Those male terminals might be easier to get.

 

[Big_John]

BTW, those connectors are called "Packard 56" connectors.

Waytek has them: 2971859 Delphi 56 Series Metri-Pack Male 12 GA Loose Terminal

Rhode Island Wiring has them too. They call them GM small blades.
Rhode Island Wiring Service Inc.

 

[rexus31]

Rexus...I was an Electro-Mechanical Technician for 30+ years at Xerox Corp. This experience certainly does not make me an expert. And I never will be an expert at anything, so...when I'm at a loss at how to fix something, I ask a lot of questions to make sure I fix it properly. Taking it to a repair shop doesn't insure that it will be fixed properly and the cost is usually insane, so I won't be taking my Fury to a shop to get this fixed. Plus...I do believe it's within my capabilities. Thanks...I appreciate your input and the photos of your fusible link but it's obviously a different setup. Now...if someone made the type that's in my 68 Fury...and posted each step, that would be the ticket!

Big John...thanks a million for helping me. You have made it crystal clear. Seeing those terminals helps me immensely. I'll be buying that terminal set you posted on e-Bay, so I can fix this the right way. Sure would be nice to find an original pigtail like in the first photo you posted, but the Dorman #85627 looks like the best I can do as I've done a bit of research on this now. I had Advance Auto order me one last night and these terminals from E-bay will be what I need to finish the job. Now...to figure out how to easily get the old terminals out of the connectors...At least I know where to squeeze/push now after seeing the terminals.

Thanks again...Bob

My post was not a dig at you in any way; merely a suggestion for you to get the repair taken care of properly. A competent automotive electrical repair shop could certainly handle this repair. If you have the chops and tools to do it, even better! Incidentally, I found a 9" length of Fusible Link wire you are welcome to. Once you get the terminals, it's just a matter of cutting the wire to the correct length, crimping the terminals with an open barrel crimping tool and inserting the terminals in their appropriate connector.

 

[furyfever]

Thanks Rexus...I appreciate your offer (and your kind words too) but I have the #85627 Dorman #16 fusible link wire coming tomorrow. I didn't take offense; just wanted to explain that I'm pretty familiar with Electrical and mechanical devices...but by all means, still an overall novice. I'm always learning that's for sure...and will be until the day I go home to my Creator. Also, I've never had to repair a fusible link before. I've been asking around at car cruises too and I'm amazed that many of the guys I ask say "a fusible what?" See where mine burned up?...right in the center...I thought that's where the fusible link was and there was regular #16 gauge wire connected to both sides of it. By what you said...that the whole length from terminal to terminal is the fusible link and how John described everything, I now understand what I'm doing. Plus...from what Gerald said...sounds like it might have shrunk too when it burned up, so I'm hoping if I make it an extra 1" longer or perhaps just leaving it the length that Dorman makes it, (7") will be ok. Like...I'd like to know HOW critical the length is. Is a factory tolerance (+/-) listed on the length of this piece? I need a 68 FSM! Like you said, sure would be nice to find an NOS fusible link like in the photo that John posted. I looked on e-Bay but couldn't find it.

Thanks again...

Bob

 

[Gerald Morris]

Got both terminals out with no problem...thanks again John. The fact that you knew what type terminals were in there and...that you included that link to the e-Bay auction was key. Both ends are the same (males). I thought the bottom one would be a female. Wire is 5" long...about 6" total with terminals. Hmmm. If I remember right, the Dorman fusible link is about 7".

6" is exactly what my sample measured. It had the yellow tag too, which is how ampacity was indicated. However you attach it, make it 6".

 

[furyfever]

Still waiting on Advance Auto to get me the new fusible link. They ordered it again...because it didn't come in yesterday...hmmm. In the mean time, I noticed this and there's very good reason to believe it's an original.

 

[Big_John]

That's definitely solder all right...

I think everyone figures you would do the typical amateur soldering job that wicks the solder up the wire and changes the resistance. Since you worked for Xerox, you've probably been through a "soldering school" or at least know what you are doing so you can do it the right way.

You're probably a clever enough guy to reuse those terminals too.

 

[cantflip]

Still waiting on Advance Auto to get me the new fusible link. They ordered it again...because it didn't come in yesterday...hmmm. In the mean time, I noticed this and there's very good reason to believe it's an original.

Interesting...

That's definitely solder all right...

I think everyone figures you would do the typical amateur soldering job that wicks the solder up the wire and changes the resistance. Since you worked for Xerox, you've probably been through a "soldering school" or at least know what you are doing so you can do it the right way.

You're probably a clever enough guy to reuse those terminals too.

I cannot recall ever seeing solder used on a connector that was factory crimped. This car is old enough however to not fall within my area of expertise and experience. I can say that your local automotive professional would not be faulted in any way if he simply replaced those terminal ends on the full 7 inches of fusible link wire...as long as he checked current flow when finished to assure he hadn't overlooked another prevalent issue. Intermittent shorts are hard to blame on a tech for not finding during the first replacement, which is why any repair without the link is unacceptable.

 

[Big_John]

I cannot recall ever seeing solder used on a connector that was factory crimped. This car is old enough however to not fall within my area of expertise and experience. I can say that your local automotive professional would not be faulted in any way if he simply replaced those terminal ends on the full 7 inches of fusible link wire...as long as he checked current flow when finished to assure he hadn't overlooked another prevalent issue. Intermittent shorts are hard to blame on a tech for not finding during the first replacement, which is why any repair without the link is unacceptable.

I have seen soldering like this on some factory stuff, but I've never really looked at fusible link terminals. But.. If you look at this NOS piece (do the magnified view) you'll see the solder. NOS Mopar 1972-74 A-Body Fusible Link

That isn't saying that crimping is the wrong way to do it.... In fact, you can make a really good argument for crimping over soldering... and you can make a good argument for soldering over crimping. If you do solder something like this, you do really have to know what you are doing.... and that isn't most of the folks out there... and that leads us back to crimping the connection.

Edit: BTW, the NOS fusible link I posted has a bullet type connector on one end and would not be right for the Fury.

 

[cantflip]

I have seen soldering like this on some factory stuff, but I've never really looked at fusible link terminals. But.. If you look at this NOS piece (do the magnified view) you'll see the solder. NOS Mopar 1972-74 A-Body Fusible Link

That isn't saying that crimping is the wrong way to do it.... In fact, you can make a really good argument for crimping over soldering... and you can make a good argument for soldering over crimping. If you do solder something like this, you do really have to know what you are doing.... and that isn't most of the folks out there... and that leads us back to crimping the connection.

Edit: BTW, the NOS fusible link I posted has a bullet type connector on one end and would not be right for the Fury.

Not arguing with any of the very good information and advice you have given John. I also can't help but apply a bit of real world to an issue like this... there is no way any shop would be puttering around this for a week or two... It needs replaced with something safe and durable, and you would have 1-2 days out of service to come up with the pieces you get to use.

Now a guy who wants to maintain a factory appearance and function would have to do lots of digging, which has been done here... simply want to convey that it would be repaired, and would have been repaired when new, by somebody working flat rate and who had no time to sit around and debate 6" vs 6 1/2"... and been done with it in 10 minutes once his parts arrived.

Not meaning disrespect to furyfever either, but the idea that he will even find tolerances on a fusible link wire is way over engineering the repair. Fusible links were used under hood to provide circuit protection closer to the battery and before the wiring entered the passenger compartment... in the days of glass fuses, they were the best option commonly and cheaply available.

If a 20amp glass fuse failed, you would replace it once, maybe do a quick current measurement, and be done if it held. Same principal applies, do not raise the amperage under any circumstances. If in a bind and you found a 15amp would get you home... no problem, just not something to leave like that. If the 20amp fails immediately, you know you have a short somewhere, don't use another fuse until the issue is corrected. Call AAA.

Modern cars do a similar thing with a fuse box near the battery that has been weather protected to some degree. They use fuses that for one reason or another were the choice of the engineer's and/or corporation that they worked for.
http://ww2.justanswer.com/uploads/heavychevy396/2010-07-02_140508_Harbor_Freight_fuses.pdf

Go to NAPA as I have in the past and buy a small roll of fusible link wire, Dorman is fine... so long as quality materials are used. Make it approximately the same length as the original, an inch more isn't going to hurt you... don't go less, but an inch that way isn't going to burn down your car either. For an "idiot resistant" repair... no solder and watch your heat gun settings for the heat shrink... For WIW the key to fusible links is the insulation not supporting flame, so the wire inside may or may not appear special.

As for the connectors, new ones shouldn't be too hard to find. If in a rush I might have salvaged the old ones... in a pinch you could butt splice a length to the short wire remaining, but I wouldn't let that happen to a customer's car and would not consider it anything more than an emergency patch.

Now I know there are a few electrical engineer's in here... please correct me as you see fit. My career was to do an acceptable repair, you fella's had to break out the slide rules and abacuses to figure out a failure resistant circuit.

 

[Big_John]

Not arguing with any of the very good information and advice you have given John. I also can't help but apply a bit of real world to an issue like this... there is no way any shop would be puttering around this for a week or two... It needs replaced with something safe and durable, and you would have 1-2 days out of service to come up with the pieces you get to use.

I don't think we are disagreeing at all here. In a commercial shop, this would be a "no brainer" and the link would be replaced in the time it takes me to type this. After all, we do know the cause (see first post) and time is money.

But.. this isn't the real world.. We have time to kick repair ideas around and get everything confused. LOL.

 

[Gerald Morris]

As a B.S.E.E., I can only affirm your recommended solution for the present. Engineers are supposed to design practical solutions, except in Germany, where they always have their heads in the clouds. (Voltaire)

I only assert that if practical, DO solder the connection, with care against allowing it to "wick" up the strands of your link beyond a few millimeters IF you want a really good connection and IFF you can do it neatly. Otherwise, crimp and be done.

Those bulkhead connections were BAD **** the day they were first excreted from some corporate engineer's R-complex. Engineers oft are forced to choose "lesser evil" options due to constraints imposed by management and sales. Such was this monstrosity. Molex connectors are no better and have afflicted mankind since the same period.

I advise all and sundry to get a nice set of screw terminals with at least enough connections to replace what you're using in the bulkhead, then re-route your wires to those. I did just so on a 1959 International which used some awful mess to go from under hood to inside and this is what I WILL do with Mathilda ASAP. I've already done away with the main power leads, brake lights and a couple others, eliminated the idiot lights in favor of mechanical sensors and sleep better for it. Sometimes an electrical fire can be serendipitous.

You might even go so far as to install nice fuse boxes at the firewall to serve for termination AND protection. I like screw terminals. Safe. Visible, reliable, allowing plenty surface area to assure good contact. Use rubber grommets to protect your wires from nicks from the sheet-metal.

Not arguing with any of the very good information and advice you have given John. I also can't help but apply a bit of real world to an issue like this... there is no way any shop would be puttering around this for a week or two... It needs replaced with something safe and durable, and you would have 1-2 days out of service to come up with the pieces you get to use.

Now a guy who wants to maintain a factory appearance and function would have to do lots of digging, which has been done here... simply want to convey that it would be repaired, and would have been repaired when new, by somebody working flat rate and who had no time to sit around and debate 6" vs 6 1/2"... and been done with it in 10 minutes once his parts arrived.

Not meaning disrespect to furyfever either, but the idea that he will even find tolerances on a fusible link wire is way over engineering the repair. Fusible links were used under hood to provide circuit protection closer to the battery and before the wiring entered the passenger compartment... in the days of glass fuses, they were the best option commonly and cheaply available.

If a 20amp glass fuse failed, you would replace it once, maybe do a quick current measurement, and be done if it held. Same principal applies, do not raise the amperage under any circumstances. If in a bind and you found a 15amp would get you home... no problem, just not something to leave like that. If the 20amp fails immediately, you know you have a short somewhere, don't use another fuse until the issue is corrected. Call AAA.

Modern cars do a similar thing with a fuse box near the battery that has been weather protected to some degree. They use fuses that for one reason or another were the choice of the engineer's and/or corporation that they worked for.
http://ww2.justanswer.com/uploads/heavychevy396/2010-07-02_140508_Harbor_Freight_fuses.pdf

Go to NAPA as I have in the past and buy a small roll of fusible link wire, Dorman is fine... so long as quality materials are used. Make it approximately the same length as the original, an inch more isn't going to hurt you... don't go less, but an inch that way isn't going to burn down your car either. For an "idiot resistant" repair... no solder and watch your heat gun settings for the heat shrink... For WIW the key to fusible links is the insulation not supporting flame, so the wire inside may or may not appear special.

As for the connectors, new ones shouldn't be too hard to find. If in a rush I might have salvaged the old ones... in a pinch you could butt splice a length to the short wire remaining, but I wouldn't let that happen to a customer's car and would not consider it anything more than an emergency patch.

Now I know there are a few electrical engineer's in here... please correct me as you see fit. My career was to do an acceptable repair, you fella's had to break out the slide rules and abacuses to figure out a failure resistant circuit.

 

[rexus31]

FWIW, the original Fusible Link harness from my '65 did not have solder on any of the terminal ends, only crimped.

 

[cantflip]

But.. this isn't the real world.. We have time to kick repair ideas around and get everything confused. LOL.

Thanks John... sometimes when I get going folks think I'm angry or "yelling" at them... not at all the case...

We do have a lot of fun reimagining the realities of our cars... and for some of us that is a big part of the fun. I just can't help that little voice in the back of my mind telling me "Okay, now how are you going to do THAT, *******...?" And yes... It does punctuate with the last word... I definitely have a track record of being harder on myself than anyone else.