Help! I'm battling an ongoing electrical problem, seems like it would be a bad battery almost. I couldn't get the starter to do anything, and none of the lights would shine when turned on. I had the battery and starter tested and both checked out fine. I replaced both battery cables and the starter cable and things worked fine for a couple of weeks, then nothing again. The lights would not shine when turned on, and the most the starter button could do is click the solenoid. I tightened the cables and got it started twice more, then nothing again. Would a poor ground somewhere else be causing this? This is a 48 F3 (know I haven't posted much in a while, you've probably forgotten about me), so there isn't a whole lot of connections. I plan to pull out the wiring diagram tomorrow and check over everything.

...Any suggestions?

 

does your year truck use a starter selonoid? My 54 would sometimes click or do nothing...I could remove the hot wire from the selonoid and hear a "click". Reattach the wire and it would start...turned out to be a bad selonoid that was just hanging up. Also had some pretty cruster wires too, replaced them as well.
If your truck is like mine, with the battery under the cab, just look inside the frame rail for the selonoid, or just follow the wire from the battery.

try it, good luck. Ed

 

Jeff, if your truck is all stock you might look at the ignition switch and/or the starter button. I've had some random problems with the button not grounding properly on the dash - rust, paint, etc.

I ended up replacing my ignition switch with a generic one that has a start position and use it instead of the button. Button is still there, but only for looks.

You should have a heavy braided ground between the intake and the firewall and have the starter brace/ground bracket that holds the front of the starter in contact with the block (oil pan rail). You can't have too many grounds.

When all else fails I take a test light or multimeter and start at the battery and work my way thru the system to find where the bottleneck is occuring. Starting system and charging system are separate circuits. If you need I'll be glad to walk you thru it the way I go about it. The experts may snicker, but it works for me.

 

Jeff, the negative battery cable goes from the battery to the starter solenoid, and from there provides power to all the circuits in your truck. If I read your post correctly, you've replaced the negative battery cable and checked and tightened the connections at both ends. Given that the starter and headlights are powered by two separate leads connected at the solenoid input, it seems unlikely that both circuits would fail at the same time unless it is a ground problem.

As Tim said, the grounds make all the difference - especially in a 6V system.

- Make sure you have a solid ground from the battery to the frame (clean connections at both ends and a good cable).
- You also need a good, heavy ground from the engine to the frame - preferably connected to the same frame member as the battery. For example, if the battery positive is connected to your passenger frame rail, connect a ground from the passenger frame rail to the engine block.
- Make sure the metal connections between the starter and the bell housing are clean and tight. That's where the starter gets its ground. You can also run a ground strap from the engine block or the battery ground frame rail to one of the starter mounting bolts if you want.
- Make sure you have a solid ground from the engine to the cab (firewall).
- Finally, any devices that get their ground from the frame or body (lights, horn, etc.) need to be checked to make sure the body or frame where they are connected is well grounded, and that the connection is clean and tight.

Good luck with the electrical gremlins.

 

Tim, I used a later 53-55 push button switch on my truck. It has a second terminal for power. It looks identical to the 48-52 switch.

 

There's some good hints at what to look for. The starter button is only a year or two old, and the starter solenoid was replaced around 7 years ago. All wiring was replaced 3,4 years ago (except for a small wire from the coil to the distributor, which I haven't found a direct replacement for). Battery is around 3 years old, I think. I have no idea how old the ignition switch is, but even with it off I should be able to shine the headlights and crank the engine, right?

Tank is negative ground now, battery and solenoid both under the hood, within a foot of each other. And it's a 50, not a 48 (see how flustered I am?)

George, am I understanding you correctly, there should be a cable between the engine and frame? Or was that a suggestion of something to add?

 

Quick update -- I checked the grounds I know of, 2 wires to a mounting bolt of the voltage regulator and the ground wire for the gas tank (due to lining). Snugged up the first a little, latter was good. Still nothing when the battery is hooked up.
Coincidental or not, I put the old battery-solenoid cable back on, then hooked the two striped yellow wires directly to it instead of the solenoid (these two wires attach to the solenoid on the same bolt as the battery cable). Now the headlights worked and also the horn. I hooked the battery cable back to the solenoid and left off the two yellow wires, and got the starter to turn the motor over, abeit very slowly. When I tried with ignition on, nothing. I tried the starter cable/yellow wires connection again, and no lights this time.

I'm still using the old breakers, under the dash, and haven't checked them yet. Could they be the problem?

 

You absolutely need a good ground from the frame to the engine.

 

When the lights don't come on... is the battery still charged? If not it sounds like the generator? When the lights would not come on, and you had the battery checked, did they recharge the battery? Perhaps once the juice in the battery is drained, thats when nothing works.

 

Dito on what Blue Dolphin said. Maybe you have a slow drain on the battery. Jag

 

I'm gonna have the battery checked again tomorrow (Carquest), see if there is anything more thorough they can do. Yesterday I checked all cables and they are tight, also checked the wires to the breakers and they are all snug. Couldn't get a sign of any electricity at all, might as well had a brick hooked to the cables.
I've kept the ground cable off when not messing around with the truck. I should hook up the charger and see what happens...

 

Personal opinion (and the set-up used by all factory wiring I know of) is to run the heavy ground cable from the battery to the engine block, with a good strap (or #10 wire) from the engine back to the frame. The starter is the #1 load and the only one that needs a #2 - #4 cable. The headlights draw maybe 25 amps, the starter can draw 200+. The engine is rubber-mounted, so some Fords I know of used a strap across the engine mount plates to complete the circuit to the frame.

I'm not sure why you would need a separate ground from the gas tank to the frame because of coating the tank; it is grounded thru the bolts at the top of the tank.

 

Have you used a multi-meter to chase down your power loss? Start at the battery, then check for juice to the solenoid? then check the switch and button, then check the starter. How are checking for power?

These 6V systems are like 12V systems on boats. Good grounds are critical if they are to function properly.

 

It sure sounds like the battery is either not holding a charge or is not being charged.

Since you had the battery checked, that kinda narrows it down. Generator.

Have you checked to see if the generator is charging your battery???? When your truck IS running and you turn on the headlights.... see if they dim and then brighten significantly when you rev the engine. If they dim and get bright a significant amount when you rev the engine, it could point to generator troubles.

 

I'd just like to add a quick 2 cents to this,

You mentioned that you checked the ground cables and they are all tight--they still might not be a good ground though. It might be worth it to pull them loose and check for corrosion etc in the cable, at teh connection point, between the connection and the frame, etc. Grounds are the most common and overlooked trouble area.
You might also swap in a known good battery that will pass a load test and then start checking your system with either a meter (preferred) or test light

Good luck...check those grounds

Bobby