This might be the dumb question of the week, but I'm really hitting a wall here! I just can't seem to get this right. I just purchased a Delco Remy alternator. (1 wire I'm not sure) for my IHC truck. How do I hook it up? The truck is 12 volt, an previous 6-12 volt convertion that never were finnished using a Rebelwire 9+3 kit. I would imagine that the connecting post that is marked BAT go to the big bolt on the starter and from there to the battery, or? Where do I connect the charge lamp? what is the "exciter wire" used for? I'm just no good at this wiring cirkus Dammit! And since I'm at it, do any of you know of any books that would be helpful. Thanks Klaus
This might require a 2nd opinion but... Yep, bat post to main post on starter. 1 post to 2 pin external regulator, and from external reg to red dash light, through to ignition side on switch. No 2 to small post on starter solenoid. The one you can arc across to fire engine. Hope that makes sense.
Or you can trade it for a 1 wire alternator and all you have to do is hook it up to + side of battery.
Although the diagram shows the #2 terminal being off to the wiring harness +12 for best results, you can also just make a jumper from the BAT terminal to #2 instead and it works fine. Terminal #1 is the exciter.
Thanks a lot Von Rigg Fink! great drawing! T2 to main buss! I'm not completely familiar with abr. in auto tech. What is main buss? Klaus
Yep, I think it needs a second opinion, No 2 wire needs to go back to 12 volt buss somewhere where it sees a constant 12 volts, don't put it on the little post that energizes the starter. Added: also don't see a need for an external regulator on that alt.
The main buss is where the rest of the car gets its 12v power from, also called a distribution block. Putting a jumper from the Bat terminal to T2 will work as mentioned above but what you don't take into account is the voltage drop from the Bat to the distribution block. The T2 wire tells the regulator when to start charging by signaling the available voltage in the system. The voltage at the Bat terminal might be 14.2v but the voltage at the distribution block may only be 12.5v or 13v due to the voltage drop. You want to use the lower voltage as the signal.
This is the same reason why 1 wires don't charge very well at idle(if at all). Yes its the exciter wire that turns the alternator on, but the T2 wire is its reference voltage. The 1 wire is basically shunted internally so the is literally no voltage drop from battery to the terminal.
I've heard about the pro's and con's about the use of 1 wire alternators.I guess i've been lucky with no voltage issues.
no it doesnt, once the alternator is excited it will stay that way till it stops spinning,, much like my brat terrible. I would however add a diode in that wire so that if there is a failure inside the alt it wont power up the starter while its running
You are correct that once the alt. is excited it will stay that way, however I think we are talking about two different wires, #1 that I was referring to does the exciting, and as long as it is fed through the circuit from the idiot light, it won't backfeed the circuit, and would not need a diode. #2 wire is the voltage sense wire and should go to a 12 volt source on the buss somewhere remote from the alt., and would serve no purpose hooked to the start terminal on the solenoid.
hmm, ok,, maybe I got my wires crossed,,,, #1 wire gets jumped to the output on the back of the alt, #2 goes to the resistor side of the starter or relay with diode. I have also seen #2 run to the start side of the starter or relay. (also needs a diode.)
Da Tinman, I think I know where you are trying to go, and it would work,#1 terminal is your exciter wire, so if you wanted to energize it from the starter with a diode you could, and #2 can be looped backed to the big battery terminal on the back of the alt., but is better off being hooked back into the 12 volt buss away from the alt. #1 wire could also be fed from the other small post on the solenoid and you would not even need the diode unless you were also using that post to feed full 12 volts to the coil during start. Just another way of doing it. Just not the way the OP was trying to do it.
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