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on a 79 Ford Truck?

Now that I have no inner fenders I'm trying to do away with as much wiring as I can. Does anyone have a wiring diagram?

I'm also installing my MSD so that will remove a good bit of wiring also.

Another question. I'm moving the battery to the bed and I have always been told. "It's best to have all your grounds connect in one spot" That doesn't mean I should have a line running from the negative side all the way to the front does it? Metal is metal! I wouldn't fiqure it would make any differancce if the battery was grounded to front or back of the frame.

Or is there a strange reason why it would?
 

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Mine was kinda like that. I had the battery ground to the engine and then a large ground cable going to the frame from the engine at the same spot.

I had just heard that the ignition system needs to be ground at the same as the battery ground. I read some where that if you didn't have it ground in the same spot that it could blow your coil or something.

I just want to make sure when I wire everything I won't be fighting electrical grimlins (sp).

When I re-wired the truck like this all of my lights got brighter. It could have been just having new cables.
 

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Ok so after some of my on searching it's not that big of a deal. I can just run the charge wire to the starter solenoid. It doesn't hook straight to the battery does it?
Does this mean I can remove my external voltage regulator? I still want all my lights.

I guess I just need a good wiring diagram for my truck.
 

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Oh Oh there ... read my latest pulling post about my rewiring of my alt...
If you have a external regulator then you can't just disconnect it .. you'll have to go with a 1 wire GM Alt. with internal regulator.

"
And then I redid some wiring that I had on the Alt. to try to make it into a one wire self-energizing one... Only problem I didn’t see was that my alt. had an external voltage regulator. And when you put power to the field wire it puts out a bunch of voltage.
I had my Batteries boiling in just a few sec. And when I put the meter on it, it read 19 volts. Oppsss undid that and then I figured it out, I had to put power to the wire that turns on the voltage regulator.. OK got that to work good now, so all I have to do is start my little pony motor and then turn on the main disconnect on and it starts to charge the batteries back up @ 14 volts. OK where good to go…. It’s only 4:00 p.m. that’s ok time for a little nap. Well the time just fly’s by when you shut your eyes for a while.. Before I knew it the track crew was there and the scale was all ready too go.. So I figured to get ShaZam on the scale to see how things weight up for the day .. I jumped in and hit the start button and nothing.. ShaZam would spin over but won’t fire up.. What the heck.
Pulled the coil wire and put a spark plug in it too see if I had spark.. Nothing….
Well it took me about 2 sec. To figure out what I did … I fried my MSD box with the 19 volts the alt. put out for that short time ."

ShaZam
 

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Discussion Starter #7
TRUKPULR said:
Oh Oh there ... read my latest pulling post about my rewiring of my alt...
If you have a external regulator then you can't just disconnect it .. you'll have to go with a 1 wire GM Alt. with internal regulator.

"
And then I redid some wiring that I had on the Alt. to try to make it into a one wire self-energizing one... Only problem I didn’t see was that my alt. had an external voltage regulator. And when you put power to the field wire it puts out a bunch of voltage.
I had my Batteries boiling in just a few sec. And when I put the meter on it, it read 19 volts. Oppsss undid that and then I figured it out, I had to put power to the wire that turns on the voltage regulator.. OK got that to work good now, so all I have to do is start my little pony motor and then turn on the main disconnect on and it starts to charge the batteries back up @ 14 volts. OK where good to go…. It’s only 4:00 p.m. that’s ok time for a little nap. Well the time just fly’s by when you shut your eyes for a while.. Before I knew it the track crew was there and the scale was all ready too go.. So I figured to get ShaZam on the scale to see how things weight up for the day .. I jumped in and hit the start button and nothing.. ShaZam would spin over but won’t fire up.. What the heck.
Pulled the coil wire and put a spark plug in it too see if I had spark.. Nothing….
Well it took me about 2 sec. To figure out what I did … I fried my MSD box with the 19 volts the alt. put out for that short time ."

ShaZam
Oh, I know I can't use the factory alternator. I was looking at a powermaster or trying to find which GM alternator to use.

I was un-sure if I could do away with my factory voltage regulator, because I didn't know if any of the other electrical systems was tied into it.

It's not. I found a wiring diagram last night and drawing my own so I can get rid of a bunch of wires.
 

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I only have 2 GM parts on my car a GM one wire alt. and a powerglide. I'm on the 3rd Alt in 2 years and the 3rd time for the tranny as well. I won't really blame the tranny much because in reality it had trouble from the torque convertor not being able to handle to power of the BBF. :)
 

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Hey Jones,

If you race at a NHRA track you need a battery disconnect since the battery is in the bed. Running that alternator wire to the solenoid will allow the truck to run even if the battery disconnect, if equipped, is installed and shut off. The alternator will provide voltage AFTER the switch, thus allowing the truck to still be powered....

Also, I seem to recall MSD telling me NOT to ground the negative of the box to the battery.....

Here's what I'd do to be legal.

1) Battery negative to frame. make sure the frame is clean!!!! I usually use some dielectric grease or something to protect the bare metal and to allow for a good connection.

2) Battery positive to disconnect switch, disconnect switch to solenoid.

3) Run that alternator wire to the positive side of the battery. That way it's on the input side of the switch and will allow the truck to shut down when the switch is closed.

4) Run a good sized cable from the frame up front to the engine. The shorter the better. The truck's power system is DC. It will "pull" it's ground through this cable when you try to crank it up. The shorter, and larger the diameter, the cable the better. If this cable gets hot when you try to fire it up it needs to be larger in diameter or the connections are not clean.

5) I generally try to make one negative, positive, and 1 switched positive connection point under the dash somewhere to wire up all of the electronics. This makes troubleshooting a breeze....

Hope this helps.....
 

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I'm concerned about the whole cutting off the engine wiring now. I now understand what you are saying about the cutoff switch. My local track is IHRA everyone runs one.

What factory part kills the engine? It's the ignition switch isn't it?

Only in the crank position is the only time the starter solenoid is energized. But in the run position the ignition is getting it's power straight from the ignition switch. Which completes the loop. So when you turn the key off it kills power going to the MSD box.
 

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The 12V supply goes through the disconnect switch first. Then on to the ignition switch, etc....

From the factory it went to the solenoid and from that same terminal on the solenoid it went to the rest of the truck....

When you flip the disconnect you just shut off the 12V power supply to the entire truck...
 
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