msd 6al no spark at plugs

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moparfanatic56

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Ok In have a 340 that I am using a msd 6al box, msd 8534 distributor and msd blaster 2 coil. I currently have it on a run stand to do my initial break in but I have no spark to the plugs. I have checked the box by jumping the leads per the msd trouble shooting instructions with a new coil and I did have spark coming out of the coil wire. I currently have it set up with a 20 amp toggle switch wired to the battery and then wired to a push button for the starter. The wire for the box that is to hook into the ignition is also hooked to the out side of the toggle switch that connects to the push button. So what am I missing here should I run a direct wire with some sort of shut off directly from the battery to the ignition wire to insure that I have a constant 12 volts or what. Any help will be deeply appreciated. As a side note I have it wired just like the instructions show.
 
I don't understand your comment about the push button. Be certain that the "big red" is wired direct to battery, or at least through a master switch, and that the "small red" is going through whatever you have for an ignition switch. Also be sure that both those wires are "hot" when the starter operates

I don't know, if you are switching BOTH the "small red" and the "large red' through the same switch, the big one may have to get power before the small one, due to the circuitry. The small one acts like a relay trigger, but I believe those are solid state switched.
 
67Dart273 said:
I don't understand your comment about the push button. Be certain that the "big red" is wired direct to battery, or at least through a master switch, and that the "small red" is going through whatever you have for an ignition switch. Also be sure that both those wires are "hot" when the starter operates

I don't know, if you are switching BOTH the "small red" and the "large red' through the same switch, the big one may have to get power before the small one, due to the circuitry. The small one acts like a relay trigger, but I believe those are solid state switched.
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The push button is to engage the starter. I do have the heavy (big) wire direct to the battery. On the toggle switch I have a wire from the + post on the battery to one of the terminals on the toggle switch. Now on the other terminal of the toggle switch I have a wire going to the push button starter button along with the small red wire for the msd box with the purpose of the toggle switch being to kill the engine. With that being said and if I am thinking right with my feeble little mind when I flip the switch to the on position I should have power to the box and to the starter button. After thinking about this it is probable that when I hit the starter button it is drawing all the current and not allowing enough to pass through the small red wire to activate the box and coil. So if I go direct from the battery to the starter button and also direct from the battery thru the toggle switch to the small red wire I should have full current to both (right)
 
Got another battery? Even a small 12V battery from a kids ride along or a scooter can power the MSD. Its about 1A draw per 1000 RPM if my memory serves me correctly. Even a battery charger could power the MSD seperately. MSD takes min 10V to work. I too am trying to figure your toggle switch between battery and MSD/Starter button. Id rewire that and run the MSD fat lead straight to battery and toggle the small red wire. If you kill the small red power to MSD youll turn it off.
 
Yeh I would hook a meter to the "big red" and monitor voltage WHILE CRANKING, then transfer to the small red and same thing. You may have a switch issue, or not enough battery, or too small cables. You want at least 10.5V cranking
 
Just a little update on my progress. I have just about narrowed it down to the magnetic pickup possibly being bad. I have done all of the trouble shooting called out by msd except for checking the magnetic pickup. All of the tests produced the spark when and where it should but still no spark when cranking at the plugs. If the pickup readings check out then I plan to check the voltage on the red wires while cranking to see if there is a significant drop off. I did change the wires to where they are both direct from the battery. By the way did I mention that I hate electrical issues but I had better get used to it,still have the car to rewire eventually lol.
 
Do you have any other magnetic breakerless dist. like a stock Mopar?

Also with MSD you CAN NOT connect ANYTHING to the coil except the two wires from the MSD box. No tach, no radio supression cap, no nothing else
 
I only have the 2 wires from the box connected to the coil. I have a sun super tach II so will I be able to connect it to the tach output on the box or will I need the tach adapter box also.
 
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