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post #21 of 27 (permalink) Old 03-28-2014, 09:45 AM Thread Starter
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Well, I tried a new coil and did not expect it to work and it didn't. Is it possible to have the starter solenoid drive the starter motor but not route power back to the coil to start the engine??


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post #22 of 27 (permalink) Old 03-28-2014, 10:28 AM
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Help! W108 Electrical Expert Needed

I wonder if your switchgear went (edit: hot spark isn't working as designed) and it is not translating the pulses so the current stops flowing to the coil.

The positive to the coil with transistorized ignition comes from the switchgear (edit for stock wiring, and with pertronix/HotSpark it gets constant 12v from the ignition) and that current should shutoff (edit: with HotSpark the HotSpark ground shuts off) causing the secondary coil to fire sending the spark to the distributor. I don't know, but I wonder if you can measure the "dwell" with a dwell meter or frequency meter at the positive on the coil. If it is 12v (on) 100% of the time, then the switchgear isn't turning off the 12v to the coil as the video in post 6 describes the function.

Edit: the pics below show 12v to the coil, and the negative to the coil being switched on and off via the pertronix-like system.

I should have read back to see what system you have.






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post #23 of 27 (permalink) Old 03-28-2014, 03:40 PM
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To test, you can run a hot wire direct from the battery to the coil. I wouldn't do this for long (a minute or so). That would tell you if it is upstream (ie. no power during cranking) or downstream (ie. an issue in the hotspark).

You said the starter is new? Did you replace it prior to or after the continuous cranking incident?

From the HotSpark manual "you can, for temporary testing purposes only, run a wire directly from the battery's + terminal to the coil's +
terminal, the Hot Spark ignition's red wire to the coil's + terminal and the black Hot-Spark wire to the coil's - terminal.
Do not leave the wire from the battery connected to the coil's + terminal for more than a minute or so without the
engine running."
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post #24 of 27 (permalink) Old 03-28-2014, 05:31 PM Thread Starter
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Originally Posted by TZ_280SEL View Post
To test, you can run a hot wire direct from the battery to the coil. I wouldn't do this for long (a minute or so). That would tell you if it is upstream (ie. no power during cranking) or downstream (ie. an issue in the hotspark).

You said the starter is new? Did you replace it prior to or after the continuous cranking incident?

From the HotSpark manual "you can, for temporary testing purposes only, run a wire directly from the battery's + terminal to the coil's +
terminal, the Hot Spark ignition's red wire to the coil's + terminal and the black Hot-Spark wire to the coil's - terminal.
Do not leave the wire from the battery connected to the coil's + terminal for more than a minute or so without the
engine running."
Thank you for the continued help guys, I really appreciate it. The starter was replaced about 10 months ago and had nothing to do with this current issue. I had a Pertronix system and thinking I burnt it out while cranking trying to start the engine, I removed it as well as the flame thrower coil and replaced it with the Hot Spark unit with their coil. I also believe that the ignition switch was bad as I could turn off the ignition and the starter would continue to crank until I shut of the battery. Come to think of it, I did notice a puff of smoke rise up from the starter area, I'll check that out but she still cranks fine, just doesn't fire. Since I replaced the ignition switch, that run on scenario seems to have been corrected. Edit: Checked the connections at the starter solenoid and while they appear old, they are intact. I know that if I hook a test light to the pos side of coil and to the neg side of battery, when I turn on the ignition, the light comes on but then goes off and stays off just before starting to crank the motor.


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post #25 of 27 (permalink) Old 03-28-2014, 07:26 PM
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Can you post a picture of your wiring setup? Sketch it out an post a picture?

I know the switchgear wiring is supposed to take current from the starter to provide extra current by bypassing the resistor providing extra juice to the switchgear. But I thought that with HotSpark or pertronix you are supposed to provide constant 12v to the coil and the ground is interrupted via the electronic ignition. (Where the switchgear wiring provides contestant ground and interrupts the positive.

So basically, I'm not sure what the starter has to do with a pertronix or HotSpark setup.






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post #26 of 27 (permalink) Old 03-29-2014, 09:38 AM Thread Starter
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Originally Posted by Fonzi View Post
NorCalSL
Can you post a picture of your wiring setup? Sketch it out an post a picture?

I know the switchgear wiring is supposed to take current from the starter to provide extra current by bypassing the resistor providing extra juice to the switchgear. But I thought that with HotSpark or pertronix you are supposed to provide constant 12v to the coil and the ground is interrupted via the electronic ignition. (Where the switchgear wiring provides contestant ground and interrupts the positive.

So basically, I'm not sure what the starter has to do with a pertronix or HotSpark setup.






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I am going to run through the Hot Spark trouble shooting list again to see if I missed anything. Will report back.
dws


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post #27 of 27 (permalink) Old 03-29-2014, 10:08 AM
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Well, reading back, I see that you say in post 13 that your wiring is identical to Luna's diagram in post 10. That doesn't have anything to do with the starter. So I guess you can see that the starter should have nothing to do with your spark... Other than the starter is the only thing that will turn your distributor right now.

If you put the hot wire from the starter somewhere it doesn't belong, you could possibly be shorting the power circuit.


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