I found that a bad wire coming off a duckfoot union (fed by pos battery cable) was the reason for no crank and no instruments. The bad news is I have to cut into and destroy the duckfoot to expose good wire for a new soldered fusible link. How do I know what fusible wire size to use? - is there a table anywhere or was there only 2-3 fusible link amperages that Dodge used (1983)? I could cut off Duckfoot and use a 4 wire block? The main looks like 10 gauge wire that feeds into duckfoot and 3 wires come off that. Is there a first gen member that has found a good way to deal with this situation? Thanks!

 

Found this valuable information on a site for Mopar -excellent information! I am going to proceed forward with the maxifuse solution -here is the link, hope this helps others with this issue

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

 

I rewired my 85 recently for that issue, also had it on my 83/ just wired in separate fuse holders on that one. On the 85 I incorporated an underhood fuse box out of an early 90s (square body) Ranger with the big "MAXIfuses". Lotsa info on those from Littelfuse. came out in like 1986 to replace fusible links as I remember.... I printed off that Littelfuse bulletin when I did mine. have it around here somewhere....
as I remember there are like a total of 6 fusible links in that area on a mid 80s truck. this is 2nd 80s Dodge truck that I wired in an underhood fuse box to, 1st was son's 89 Ramcharger that we converted back to carb and 4 pin Mopar ECU from that horrid TBI setup. (we also put a 408 CID stroker in that truck too) my 85 is a Slant 6, will probably stay a Slant 6.

 

Thanks for the info VolareDon - yesterday, I spliced in the new primary and fuse holder (solder connections and heat shrink but . . . . the Napa auto parts counter guy gave me a fuse holder for mini fuse (30amp) after I had done all the hard work but truck ran fine with it and fuse did not blow. I can add a maxi 40 amp fuse using spade connectors but isn't 40 amps 40 amps regardless of fuse size? The link I provide above was excellent but the writer recommends 12 gauge wire for the primary wire on each side of the 40 amp maxi fuse but 12 gauge is supposedly only good to carry 20 amps . . . . more confused than ever now . .

 

Well yeah 40 amps is 40 amps. But just because a circuit is wired for it doesn't mean there is always that much going thru it.
But between mini fuse, regular fuse and maxi fuse of a given amperage/ look at the size of the contact area where the fuse plugs into. The maxi is much bigger as is what they call a j case fuse as compared to the mini. Which one do you think will get hot and burn easier? The one with less contact area!
I wish I could find the bulletin from littelfuse that I had then but the maxi fuses are somewhat of a slow blow fuse as the fuse links are, the maxis were designed as a replacement setup for fusible link, the smaller one will blow faster at max rated capacity in a given amperage.

I work on alot of (ugh) Fords at work. The 09s or so and up have a problem with the fuel pump fuse burning contacts in the fuse box and they have a bulletin to switch the contacts to an unused fuse slot that takes a different style of fuse (bigger) than originally wired to within the same fuse box. Constant high draw on the fuel pump circuit.

 

Thanks Volaredon, makes sense. Last maxifuse holder I saw had like 8 gauge tails! Too big to add (wire wise)so I may just solder on some female spades that can accommodate the blade width on a maxi, heat shrink spades, etc. Thanks again!

 

Every wire that went into that fuse box that I wired in was either 10 or 12 ga. There were a few smaller ones that went to a couple of standard size blade type fuses in the box. I cut the harness of the donor truck back about a foot of wire beyond the fuse box out of the truck it came from. I looked for a simple smallish fuse box, some of the under hood fuse boxes are kind of obnoxiously big, and with a carbureted truck with no computer or anything that wouldn't have been necessary. I also got me a factory service manual for the truck so I had full wiring diagrams while I did the fuse box transplant. NOT a HAYNES they absolutely suck.

 

Myself since I am replacing the LA-727-NP208 with a Magnum-A518-NP241 in my 1985 W150 and will be running a electric fuel pump to the Holley 4160 along with converting to HEI. I have pulled the Power Distribution Center out of a 97 Ram 1500 and will be wiring that in using the relays for the fuel pump, headlights, fog lights, HEI, and the starter relay. I also pulled the alt wiring charging wire from the 97. I will be using the 1985 voltage regulator but it will have a relay, the ignition switch will just turn on the relay and then it will sent battery voltage to the regulator. This is how Dodge ran the voltage regulator when you had the Heavy Duty package or the Snowplow package on the 1st Gen Trucks. The Power Distribution Center has the modern fusible links the great thing is the wiring colors from the Power Distribution Center match the wiring colors that were used in 1985 between the Duckbill and the firewall connector.

 

Are you staying carbureted? When I redid my truck and my son's, I walked the local junkyard, and picked something that seemed "just the right size" for what I was trying to accomplish// I used to have a 97 1/2 ton Dodge 4wd, and it seems like I thought that under hood fuse box would be too big for our needs, especially not wanting to convert to injection. As it is, I have a couple of empty fuse slots for future use/ and it wasn't that hard to draw up a diagram with what circuit went to what fuse slot. I only used about 8-10" of the wiring that came with the fuse boxes, didn't really care about wire colors out of the fuse box, since I tied it in to the rest of the original harness/ so I can still use the original color chart for the truck I have. Though I did write down on my diagram, what color truck wire went to what color donor fuse box wire.
i basically decided what fuse slot to wire a given circuit to, by the wire gauge size coming from a given fuse. I was able to match up like gauge size wire from the truck harness pretty well, with what I had furnished from the fuse box. And considering that fusible links are 3 gauge sizes Smaller than the parent circuit, it probably wouldn't have hurt to go down 1 gauge size at the fuse box vs what the truck had, since I was going less than a foot to the fuse from there/ but I wouldn't go any smaller than that. Going the other way, bigger feed into the fuse box than the parent wiring, won't hurt a damn thing, especially since there is a fuse at the other end of that wire. I think all the truck wires were able to mate to the same gauge size wire coming from the fuse box in my case. So definitely no worries about under sized wiring in any circuit.
A bit issue that I had was the number of wires in the truck harness that simply had split, cracked insulation from being 30-some years old, I went thru the whole thing before I got to the point of thing into the fuse box.
The biggest thing is to get rid of the original fusible links and replace them with something easier to service that is designed/meant to take that kind of electrical load as opposed to exactly what the replacement fuse box came from. Though I would have had a harder time (in my head anyway) grafting something from an imported vehicle into my Dodge. Defecting to a part from a ford is bad enough there...... Well you will never see me put anything but a Dodge engine in my Dodge, these people who put Chevy engines in anything that isn't a GM, **** me off.but that is a different story.