73 dart sport wiring problem???

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mr.demon

mr.demon

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Hello all, I got a 73 dart sport that i bought as a painted shell with everything else in boxes. Anyways got my 340 and tranny in. We wired everything up and I cant make the motor turn over from key. I have 12 volts everywhere under hood and at amp guage. I haven't seen this problem yet. With key in off position and battery connected the ballast gets really hot and the only two ways I can turn motor over is arc the starter relay or touch a jumper wire from altenator to starter relay. Does anyone know where to start looking for a bad wire? Oh, and nuetral safety switch is good also. Sometimes I can turn key on and get the buzzer until I try to turn the key over to run then nothing happens. I'm pretty frustrated so I'm resorting to asking for help. Thanks, Jake
 
Find the yellow wire at the starter relay. Attach a test lamp there where you can see it. Turn the key to start. If that light comes on the ignition switch etc.. is good.
 
Thanks, but that wasn't it. Are there any grounds that absolutely have to be hooked up besides the amp guage and the little ground going from steering column to dash frame? Or some other thing that is easily overlooked? I have a new engine forward harness, ballast, positive cable, ecu (brain box), voltage regulator, and ignition harness from key switch to where it plugs into the under dash harness installed now and still same problem. I don't have the rear of the car wired up yet ( tail lights side markers etc.. hooked up would that cause my motor not to fire from key switch??? Thanks, Jake
 
I expected "Yes the light came on" or "No the light didn't come on". Then we go from there.
"That wasn't it" doesn't tell me squat ! Maybe someone else here can help you.
Good luck
 
You sure your harness is the correct one(s)? What do you have for a diagram? GET a shop manual, either on CD or a printed rpop.

FIRST thing to do is figure out why the ballast ??gets hot?? with the key ??off??

Red is right. "That wasn't it" does not tell us much.
 
I'm sorry i didn't explain it very well. Yes the light came on. I have 12 volts from the battery all the way to the amp guage. I did notice the brown wire from the bulkead to the starter relay pulled out of the bulkhead. Isn't the brown wire for the nuetral safety switch? I plugged it back in and checked for continuity and meter said it was good. I have a wiring diagram for my demon that im working with now. Is the wiring alot different from a 71 demon and 73 dart sport? This may be my problem if everything is different but the wire colors on engine forward harness all match up. I hope I didn't look like a smart-*** with my "that wasn't it" post. If I did I apoligize. You guys are really knowledgable and I've learned alot from past posts and want to continue doing so. I'm only 26 and trying the DIY approach instead of paying people to do the hard work for me. This wiring problem is the only thing holding me back from hearing my 340 run for the first time since I picked it up from Buzzard Racing Engines last summer. Normal for you guys but a dream for me if I can drive it before the end of summer. Thanks for everything, Jake
 
The brown or tan may be either the window washer pump, or the coil resistor bypass circuit.

To find out, probe the bulkhead socket where it enters and twist the key to start. If it's hot in start, it's your coil resistor bypass, which hooks to the coil + side of the ballast resistor

If it's the washer pump, it will be powered when you punch the washer button

To checkout the start circuit, go to the start relay and identify the push--on connectors. One should be yellow, and is the "start" power coming from the IGN through the bulkhead

Clip your test lamp on that yellow and twist the key to start. It should be "hot" in start

If so, hook the yellow back up, unhook the other "push on" wire on the start relay (which goes to the neutral switch)

Clip that terminal on the start relay to ground and see if the engine starts with the key. IF not, try the light first on one, then the other push on terminal with key in "start."

One terminal should NOT light, IE the one you clipped to ground

The terminal with the yellow wire SHOULD light in "start."

IF this happens, and no crank, you most probably have a bad start relay

To make ABsolutely sure, jumper the "big stud" to the "square" terminal, the starter should crank.

IF so, replace the relay

If clipping the NSS terminal to ground causes the relay/ starter to operate, you either have a bad NSS, bad wiring down to it, the shifter is out of adjustment, or the "comb" in the trans is damaged
 
Members here have put that brown wire for the washer pump on the ballast resistor, extended to the starter relay or the neutral safety switch, and re routed to the oil pressure sender too.


You couldn't have known by the wording in my earlier post that I was in a trouble tree dianosis train of thought. I do that to limit my typing to only what is relevant.
 
Ok, thanks guys. I will check everything out really well next time I get to the shop and post back with a yes and really excited story or a no and give a detailed explanation of what I found from the info that you guys gave me. Again, thanks for everything.
 
You are confusing me more than anything. What do you mean the amp gage is grounded? That isn't right. There should be a direct connection from BATT+ to the ammeter, so having +12V there doesn't tell you much.

Your current problem is wiring to the starter relay. It sounds like your ign key is working since you get +12 V on the yellow wire when you turn the key to "start". Elaborate on what you did to verify "NSS is good". Do you measure +12 V on the big stud of the starter relay? When the starter relay actuates, you should hear a clunk from the starter solenoid, and if the starter is good and engine not jammed, it should then turn over, or at least try to.
 
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