demon 340 wont start, no spark

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eric72demon

eric72demon

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I recently got my demon 340 back together, rebuilt eng/trans. new petronix distributor & coil, battery, ignition module, voltage regulator, engine wiring harness, ignition switch, battery cables & ground strap from block to body. I have been trying to get the eng. to fire off but I have no spark out of the coil. I by-passed the ballast, blue wire to brown wires, I have 11.8 v. to the coil brown wire, still no spark out of coil. I put the original coil/dist. back in & have the same problem. this may not relate to the issue, but the brown/yellow striped wire from the trans. switch goes up into the firewall & into the dash where I lose it. this wire should go from the trans. switch over to the starter relay. I have a 72 dodge demon repair manual & it shows the wire going from trans. to relay, not into the firewall. I currently have the brown/yellow wire going to a short ground & the engine turns over fine.
Any help would really be greatly appreciated.
 
The possibilities are almost endless with a self wired never ran before project.

Maybe start with what ignition system you are running and if it has been modded with wiring or anything else you can tell us or even better show with pictures.
 
If you have the correct wire, the Brown/ yel (see page 8-147, engine bay) goes from the center pin of the neutral safety switch to one of the two "push on" terminals of the starter relay. This provides a ground to the relay in park and neutral, and allows the relay to function

If this is screwed up you can get the engine to crank with the key by simply temporarily grounding that terminal of the starter relay

This WILL NOT have any effect on a spark problem

Do you have any reason to believe the wiring is hacked up? Evidently you have operated this car previously?

"Old distributor" Is this points or what?

What all is connected to the coil NEG? I would disconnect tach if it is hooked up, and ONLY connect the ignition system, IE the black pertronix wire, and by the way, the coil mounted capacitor / condenser should connect to the coil +. I would ALSO leave that loose for now

Can you provide a link, ETC to the pertronix product? Is this a two wire black / red deal?

If so, black goes to coil NEG, red goes to coil + AND to 12V
 
Sounds like it ain't firin.
 
I'm kinda in the market for a Demon. Running or not. Actually, just a roller, would be ok.
I know Rochester is a tad far from me, but if you trailer up here to my place, I'll look it over.
I'm kidding.
I'd just like to add, that, if it acts the same with both systems, and that the same coil is NOT used with both systems, then IDK.
Here is a real sneaky coil test, that's got me out of a pickle many a time; Just lay an 8" or longer flat-bastard file on a grounded-to-battery surface. Then take all the wires off the coil neg. terminal. Run a jumper from the coil neg. over to be long enough to drag over the file.Take the coil hi-tension wire out of the cap and near ground it to the engine; that is to say secure it with about a 1/4 inch gap to ground.Hang on to the jumper wire, and power up the coil(turn on the key to run). Here comes the cool part. Lightly drag the exposed bare wire of the jumper along the file. You should see a stream of sparks issuing from the hi-tension coil wire, as the jumper "makes and breaks" the low voltage connection. Please be sure to not burn your car down by accidentally setting the carb on fire.This works on all OEM type canister coils.Never tried it on an E-core.
I know; it's hard to imagine both coils being bad, but you gotta start somewhere.And by leaving all the wiring alone up to the coil plus terminal, you have just proven it's ok. But on the off chance that the coil plus is not receiving enough current, if the above test fails to wake up the coil, then jumper battery voltage over to it, and repeat the dragging wire test. Still no spark means coil is fubarred. If it sparks now, the wiring is compromised.
What I mean is; You can sent 11.8 volts through a wire .005 in size but it won't spark the coil.Your multi-meter will say "hey I got all the volts I need", but the electron flow is too small to accomplish any work.
Ps this looks really cool in the dark
 
the car was originally 6 cyl. with a/c. It ran before I tore it down. it has the electronic distributor system. I called laysons restoration in Tacoma & was told the brown/yellow wire that is on my car and goes into the firewall, not over to the relay, has to do with the reverse lights. the tech I talked with got the info. from a 73 dart wiring diagram. my old harness had the wire attached to a blue/white wire in the eng. harness going to the relay. it looks all stock, but I can't find a match in my manual. i did run a wire directly from the battery to the coil & still no spark. thanks for the help.
 
eric72demon said:
i wired the distributor using the dodge connector, the orange/black rubber coated push together one.
Click to expand...

You are going to have to cough up more information. If I have "crystal balled" this correctly, this is NOT the way to hook up Pertronix.

We need to know WHAT you have, and exactly what you hooked from one end to what at the other end.

To repeat, I do not know of any Pertronix product that hooks to the Mopar distributor connector
 
If I have "crystal balled" this correctly, this is NOT the way to hook up Pertronix.

To repeat, I do not know of any Pertronix product that hooks to the Mopar distributor connector
Click to expand...
It sounds like he soldered in the Mopar zigzag pull apart connector to connect the dist to the coil so he can seperate/unhook/pull the dist somewhere on down the line when needed (which is a smart plan). If that is correct then he is fine. just connect ign1 "run" and ign 2 "crank" together if using the Pertronix (no ballast) coil and run that power line to the coil positive primary terminal
 
brown or brown w/ yellow is neutral safety. Reverse lamp wiring is the other 2 wires at the trans mounted switch ( purple I think ). As said above, nothing to do with lack of spark.
 
RR
When I connected those two wires together, my starter relay was full time energized, which with a 4 speed and clutch-switch, would engage the starter everytime I stepped on the clutch. I imagine with an automatic, the starter would be engaged anytime the tranny is in Park/Neutral.
To remedy that I ran a separate NO relay triggered by the crank circuit, to power up the ignition. Presto!
 
thanks for all the replies. I finally found the problem. the ignition switch wiring connection caused the system to not have the voltage thru the firewall connection. I am going to replace the harness for the dash.
 
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