update on valiant stall

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fonzy

fonzy

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a little update, the car would run and idle fine for about 15-20 min, then it would just stall like someone shut off the key. we had recently just replace the ballast resistor and mucked with the timing(I am pretty confident the timing is fine and the harmonic balancer had just slipped). while attempting to figure out the ballast resistor was bad we had purchased a new ignition coil. so, we checked the carb, fuel going in just fine. the car wouldn't start after the stall, the spark was erratic after the stall. so, we put the new coil on and the car idled for one full hour, no issues. I think that fixed it. now, for a stupid question. I know the coil takes 12-14v and bumps it up to 26,000 or so...I expected the coil to be warm, however it was so hot to the touch you could barely touch it for a split second. is it supposed to be that hot? could it be wired to the ballast resistor incorrectly? I am checking the voltage coming off the resistor tomorrow (working today and I need a more accurate volt meter). thanks for the advice guys.
 
No, your coil should only be warm to the touch, not hot enough to burn. Don't freak out when you measure the voltage coming off the ballast and it is only 7-8V. That is normal in the run position of the ignition switch. Ma Mopar did it that way to make cold starts easier. In the run position the ballast resistor is in the circuit and cuts 12V down to 7-8V. In the start position the ballast is bypassed and full battery voltage is applied to the coil. This solves the problem of no fire when it is really cold and the battery voltage drops to around 10 volts when the starter is engaged. At those voltage levels a 12V coil will barely fire while a 6V coil with the same voltage applied would light up Times Square. Stock Mopar coils are 6V, not 12. Just one of the little touches that make a Mopar special...
 
Use a voltmeter to check the voltage at coil + while running; it should be lower than 12v as noted above by grumpus. If close to 12v or more, you have an ignition switch problem or a wiring issue putting 12v to the coil+ all the time. Good that you caught this.
 
another question, could they have given us a 12v coil? and if so then would the lower voltage cause the coil to overheat?
 
also, i should add this vehicle has the orange ignition mod from a 76 slant, there are no points on the distributor.
 
ok, pop put his volt meter on the resistor and it was wired up to the 12v side, moved it to the 9v side and it's warm but not as hot as it got last night. one more down, next. lol.
 
the resistor shouldn't have direction right? what I mean is I put the wires back exactly as they were originally, so my guess is whoever did the wiring before put it on the wrong side of the resistor as well. which would explain why the original coil shot craps. and thanks guys, I am still going to clean all those bulkhead connections and re-run the fuel line, per allpar.
 
Right, the old 2 prong resistor (single resistor) works the same in both directions. Now I see what you meant by changing to the 9v side; yep that would do it.
 
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