Bad Brown Wire

[ta TACO]

Ok, so I recently purchased a 68 F-250 Camper Special and started going through everything. I noticed that the brown wire going to the solenoid was burnt through the tap making up the harness. From what I can figur is that this is a heater wire. This wire goes from the solenoid to a box on the pasenger side on the cab under the dash to behind the gauge cluster on the dash. Is there something that could have gone bad in this system? I really suck at wiring and could use some help . As far as the heater it's self, the blower moter will turn on and I just fixed the inlet valve to the heater core. Also, when I was taking everything apart, I found about 3 lbs of sand and debris in the fenderwell where the inlet is for fresh air. So that was completely stopped up. I'm thinking that motor could have been working to hard and overheated the wire. Any advise would be great.

Thanks in advance,
Davin.

[fordman]

http://www.fordification.com/tech/wiring/68-09.jpg and http://www.fordification.com/tech/wiring/68-18.jpg
there are two brown wires up front. one is the heater wire. (wire 181) it comes from the fuse panel up to the heater. the other brown (wire 262) wire comes from the solenoid all the way to the resistor wire at the firewall. it is used to provide 12 full volts at start up only. after that the wire isnt used. only when starting the truck. the other brown wire i can think of in the cab is the tail light wire. it runs fromth ewmain harness near the turn signal swithc out the fire wall and to the rear brake lights.

[ta TACO]

This is the brown wire coming from the solenoid. What would cause it to burn up? Can I just replace the wire and call it good. There are still some crazy wires under the dash. I found one wire that was soldered into two wires, jumping the two together. Not sure if I can just undo this or what. Thanks for helping fordman. You always seem to be on here giving good info, I appreciate it.

[fordman]

maybe holding the key on too long would cause it to burn up or the solenoid got stuck and kept power going through it. or a surge of some type maybe.but yes its just a wire. it can be replaced.

[ForingaMex]

I wonder too what would make that brown wire overheat and melt the insulation. My truck is the same way since I bought it and until recently I didn't even know what it was there for. At first when I discovered it I was worried that it might short out all kinds of wires in the loom but everything worked well so it's still that way. I hope to take the loom apart one day and replace that wire. We'll see.

[Thunderfoot]

If you were to leave the key on (run) with the motor off for a long period of time it wouldn't cause a problem with this wire but would with the resistive wire from the ignition switch if the points were closed, it would/could overheat this wire as it is not fused and with the points closed it is a short to ground so it could overheat and melt...

But for this brown wire it could be a cause from the starter solenoid having power to this wire all the time even when the engine is off and not cranking. If the engine is off and the points are closed it would overheat this wire and melt it. If the engine is running it wouldn't hurt it but it would be hard on the points having 12V to them all the time.
Check that terminal on the solenoid and make sure it only has power when you are starting the engine and not all the time... could have happened with a bad solenoid before you got the truck...

Only other thing would be a lot a cranking on the motor to start it with the points closed or shorted to ground, it would take a bit but it is possible...

If this wire does short out, it will kill the spark to the motor so be sure that it doesn't short out on anything if you have exposed wires on it.

[ta TACO]

Thank you Thunderbolt and Fordman. It does take some cranking to get the truck started, so this could be the problem. I'm working on getting ever thing back to stock. As good of a truck it is, it sure has some electrical issues. I'm learning the wiring diagrams aren't as bad as my Toyota, which is nice. I was practicing my soldering technique to fix the wire, but I guess I got the wrong kind. I bought acid core and not rosin core. Not sure if its a big deal, but decided to hold off.

[Racer Z]

If this brown wire was cut or broken would that cause an engine to start hard? My engine is fresh yet it has to crank way to long to start sometimes.

[Thunderfoot]

If this brown wire was cut or broken would that cause an engine to start hard? My engine is fresh yet it has to crank way to long to start sometimes.

When the engine is cold or if it was a bit flooded... Yes this wire being broken or not hooked up could make it harder to start. This wire gives the coil full 12V during cranking which gives a hotter spark to the plugs to make it easier to start.

[ta TACO]

So I got to the replacing the wire. OK, from the solenoid all the way to the yellow connector on the passenger got very hot at one point, or several. I replaced the wire from the solenoid to about 2 inches before the connector. I also had to replace about 2 inches after the connector. I'm hoping I don't have to strip the entire harness to place the whole wire. The wire all the way to the harness and beyond had been hot and the insulation had mended to the internal wire. I'm hoping I won't have issues since I cleaned and soldered my connections. Now I went to the coil. I noticed that it had been re-taped before. It was ugly! Someone had takes the wire to the coil and the oil pressure sending unit and just twisted the fried mangled wires together. There was also a couple of wires going to the ignition switch that someone had taken another wire and jumped the 2 wires together. I'm guessing to get power to the 12V to start the car. I'm hoping after fixing the wires It will start. OH yeah, they had also tapped into the fuse panel a wire to the coil. Fingers crossed.

Does any know if this could solve my no gauge lights problem? I'm just looking for some moral support on this one

Thanks,
Davin.

[fordman]

which gauge? all of them? or the gauge lights? what igniton is it that ? points or electronic?

[ta TACO]

None of the gauge lights work, but the bulbs are good. The only gauge that works is the fuel gauge. I know why the speedo doesn't work, NO CABLE . I still have points. Now I know why the temp and oil pressure gauge don't work. The water was burned up, the oil is disconnected. Haven't made it to the ammeter yet. There was one of those 3 gauge pods attached under the dash, but they didn't work either.

Davin.

[Thunderfoot]

I wondering if the Pink Resistive wire to the coil is still good and in the circuit or if the PO wired around it... This wire drops the voltage to the coil so that is has around 6-9 volts instead of 12... This Resistive wire should be inside the cab harness from close to the ignition switch to the firewall, with the brown wire being that bad and with the other stuff you found I'm wondering...
If you look at this diagram http://www.fordification.com/tech/wiring/68-09.jpg you see wire 16 Red/Green striped from the ignition switch, turns into 16A Pink Resistive inside the cab, then at the connector you see that Brown wire 262 also connects in with 16A then it is back to 16 the Red/Green striped wire to the coil. If you follow 262 back it goes across the inside of the cab and then out the fender to the starter solenoid. One note here on the 16A wire is that it may not be in the section of the harness as in this diagram it may be right off the ignition switch it seems to change with some years just not sure when but some have seen it right off the ignition switch, yet FYI...
If the Pink wire was fried or wired around you can get a replacement from your local parts store it is a common part for fords.

Crossing my fingers for ya that it all works out and you get it back as it should

[ta TACO]

I did notice the 16A wire, but it looks to be light brown. May be from getting hot. So I can go to oriely's and get that whole section of the harness, or just resistive wire. Is that a word, resistive? Oh well I'm rolling with it. I was also thinking that I need to replace the entire wire and the connector since NOW, I have no juice to the starter . Like I said, I only replaced about 3-5 inches past the yellow connector under the dash on the passenger side. I also notice that there are only 7 wires connected to the ignition and not 8. That diagram you supplied is what I have been using to redo my wires, but it does not show the wire colors going to the plug. OK, and heres the whopper. The alternator is new, but I noticed there was 2 wires coming from a plug and another bolted going to the solenoid. So I did some research. Come to find out AC Delco part 334-2112 is a damn Chevy alternator! Oh yeah, since I replaced wires 39 and 31. I checked them to see if they had power. They do, but it is a pulsing power. Is this normal. I'm beginning to think I should have left everything a mess. At least I would be able to start the truck .

[Racer Z]

Nothing wrong with a Chevy alternator. They used it because it has an internal voltage regulator unlike our Ford with an external regulator. It's simpler and looks cleaner. So, yes, it only uses two wires instead of our three. And your description sounds like it's wired correctly.

No, it's not wired correctly now that I think about it. It will work, but the amp meter won't work. This thread is about the amp meter, and might help you with the wiring. http://www.fordification.com/forum/view ... =8&t=55960

Most trucks/cars use a "ballast resistor" which is a big ceramic thing that bolts to the inner fender panel. Our Ford trucks use a "resistive wire" that's hidden somewhere. I think Thunderfoot said it's under-dash. Both do the same job, one looks nicer.