Hey Sparky - this ought to right up your alley. After mucking about in the engine bay trying to plug the oil leak from the rear intake manifold seal, I tried to start my truck. I got sparks from the negative battery post and then nothing. I cleaned the battery posts, and all the connections on the solenoid, put the charger on the battery and got sparks again. No lights, no radio.

After checking wires for a bit the truck started. I must have jiggled the offending wire loose. My guess is that I have a potential short somewhere. What I don't know is how to find it.

It's kind of ironic that I am having this problem, as I am the guy who accidentally posted about my 89 F150 in this forum about a month ago with a similar problem. That one turned out to be a bad connection on the "s" post on the solenoid - I had loosened it while replacing a heater core. This problem in on my newly acquired 68 F100.

 

If you have sparks at the battery post, you probably have a loose/dirty connection. Do you have a frayed cable or one of those add-on connecters ends on the cable. If so, toss it and spend the very few dollars on a new cable.

 

Thanks,

The battery cables and wires are not very good on this truck, so that would not suprise me. I am seriously considering totally re-wiring the truck. (if you knew how electrically challenged I am, you would know that's saying something). TruckHaven advertises for wiring stuff but only up to 67. Anybody know who carries for 68?

The post that was sparking was the negative post - no extensions or anything on it. The PO of this truck has an alligator clip on the positive side - I think it runs the CB.

 

Just as stated you most likely have a bad ground wire. Probably wasnt making a good connection at the battery - , hence the sparks as the electricity tried to find a path to ground.
Replacing the old battery cables, and ground cables sounds like a good investment

Sparky

 

For my negative I use a marine terminal with a 3/8 stud and wingnut. Then run 6/4 gauge cable to the engine (alt. brcket), frame, and body. Then a 12/14 gauge wire to the base of the voltage regulator. Coat both sides of the connecting lug/washers with silicon grease and top the bolts with grease or something.

 

>something). TruckHaven advertises for wiring stuff but only
>up to 67. Anybody know who carries for 68?
>
>
Most of the "harnesses" you will find are universal. This means you must reuse all your connectors by splicing them on. An easier way would be to get a complete harness out off a junk truck and between both harnesses make one good one. Most recyclers let these harnesses go for next to nothing. My extra harness they gave me for free because I bought the dash.
Russell
1968 F250 LWB 300-6

FORD=First on Race Day
#88 Dale Jarrett
#21 Elliott Sadler
#97 Kurt Busch
#28 Ricky Rudd

 

[updated:LAST EDITED ON 04-Dec-02 AT 10:59 PM (EST)]Most junkyards around here don't carry stuff this old, but if I find one, what is included in a wiring harness? Wires and connectors for EVERYTHING on the truck? Not just engine stuff, but tailights, radio, speakers, etc? What year truck should I look for, mine alone or are they interchangable and if they are, what years work for a 68 Ranger? Should I be expected to take it off the truck? I imagine that if they let them go for cheap, they expect you to pull 'em. That would be more than an all day job for me - as you can probably tell by the electrical questions I ask.

 

67-69 would work. 67's are a little bit different. 70-72 is totally diferent when it comes to the dash gauges.
Russell
1968 F250 LWB 300-6

FORD=First on Race Day
#88 Dale Jarrett
#21 Elliott Sadler
#97 Kurt Busch
#28 Ricky Rudd

 

Well wait a minute! No need to wipe the slate clean and start over. Just do the battery cables, starter cable and solenoid connections. You can buy new battery cables and cut them to the right length and install a new eye with a propane torch and a little solder. Same goes for the starter cable (two eyes). Slap on a little heat shrink and you have a custom cable for just a few bucks. Get a crimpier (everyone should have one) and put ring connectors on the start and run wires at the solenoid. Just for grins add a ground wire between the cab and the frame. This may already be in place just behind the carburetor on the fire wall. I like to add an extra ground strap between the transmission and the transmission cross member. After that address the electrical issues one at a time. A new fuse block with the blade type fuses is also a good investment on these old trucks. I have seen these advertised for less than a 100 bucks. I also carefully pull the bulkhead connections (engine side), clean them with a brass brush and add plenty of dielectric grease and plug them back in. You can always install a complete new harness, but for now just solve the problem and run the truck. Easy rule "hot connections are a problem" "sparks are a problem".
William in Atlanta

 

[updated:LAST EDITED ON 05-Dec-02 AT 04:12 PM (EST)]Thanks guys.

The big (battery) cables I can do, it's the little ones that scare me. The ones that disappear into the loom and I have no idea where they go....

It sounds like lots of grounds is good. I will redo the battery cables, I also discovered that I now must do the "shift lever jiggle" to start the truck. This is the neutral safety switch, or somesuch, and resides in that deep dark tangle of wires known as the steering column, yes?

The 68 came without a front bumper, and there is a ground wire from the valance (the piece between the bottom of the grille and the top of the bumper) to the frame where the bumper mounts as well.

I guess I'll just take it one step at a time.

 

Regarding your having to jiggle the shift lever to start motor: The neutral start switch is located on the top side of the shift column about a foot up from the firewall. (The wires are separate from the loom running up to your turn switch). If you look under the dash you will see it. Notice the transmission selector arm which comes up through a slot in the column and contacts the neutral switch. The switch is held in place with two 1/4" hex screws. You can slightly loosen the screws which allows you to slide the switch from side to side to adjust the start position. Be CAREFUL. If you slide it too much you will find that that you can start the motor in gear-either Reverse or Drive, depending which way you overcorrected. Properly adjusted, you should only make starter contact when the shift lever is in Park or N.

 

Thanks Sully!