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Discussion Starter · #1 ·
I'm about to get to the trying to make my 4bt Run step in my project, and I need some help. I searched the forums and the FAQs for a good list of wires needed to run and wiring schematics, and some info on wiring the starter circuit for a 1994 Dodge Cummins starter, but couldn't find anything. Here's what I have gleaned so far:
-I know I need 12V going to the Fuel Cutoff Solenoid when the key is in "Start" and "Run" positions.
-I know I need to wire the alternator to charge the battery (not needed to run, but needed for accessories, etc)
-I know I Need to wire starter - battery- relay circuit.
I've done a lot of fabricating and troubleshooting on vehicles, but never wired these types of circuits before. So, two questions.

1. Aside from ancillary stuff like gauges, do I have everything that I need to run?
2. Does anyone have any good basic schematics of the Alternator and Starter Circuits?

Thanks for the help!
:beer:
Tim
 

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Here is a little of what I know that might help.

1. You need a "key-on" power wire to alternator to power up the alternator on start-up, otherwise the alt. will never put out a charge to the battery. The post on the back of the alternator should be connected to battery positive. It should also piggyback onto the connector on the side of the alternator.

2. Yes, you do need the alternator to charge the batteries to keep the engine running, however, it takes very little power to keep the fuel solenoid open.

3. The starter gets a positive cable from the battery to the big post on the starter. Then the starter "key on+start" wire needs to be attached to the starter solenoid. The starter will ground through the engine, so be sure your ground wire from battery is connected to the engine.

4. I have made up some schematics for starter and alternator circuits to help my dad with his project. If you think you need them I could get them up on this thread, but it may take a few days.

Good-luck with the FJ! Too bad it's not a CJ ;)
 

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The starter will ground through the engine, so be sure your ground wire from battery is connected to the engine.
If you run your battery negative cable directly to the engine (which I do!), don't forget to put an equally beefy cable from the engine to the frame / body (I usually do one to both, just to be sure).

Paying attention to the "ground" side of your wiring will pay off in the end...
 

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Discussion Starter · #4 ·
Good-luck with the FJ! Too bad it's not a CJ ;)
Thanks for the help. If you get ahold of those schematics, I'd certainly like to see them. Don't go out of your way too far though.

Actually it's too bad your CJ isn't an FJ ;)
Definitely nice project though, I'm jealous if you have anything running and driving with a 4bt :grinpimp:
 
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