Re: 1934 1101 coil problems, HELP!

Posted by HH56 On 2021/8/16 18:16:49

If they are getting a constant 10-11 volts they would most likely overheat. If that is the case something inside could be expanding and acting up or maybe the insulation is reaching a point where temperature is causing it to break down.

I would expect the early coils and probably the repros which are most likely made using modern coils as a starting point would prefer the same 6-8v that the current 6v coils prefer and that is what they should get with the direct feed. Modern 12v coils also prefer a lower voltage to keep from overheating or having a lot of current flow thru the points. They require some kind of internal or external ballast resistor or a special resistance feed wire to provide them a steady voltage of around 8-9v.

I would suggest measuring the coil supply voltage very carefully when at rest and when the engine is running and maybe also measure one or two other places not directly connected to the coil. Reason for another measuring point is to find out if voltage is actually out of spec thruout the system or if when the coil's magnetic field collapses, back emf from the coils is also being read by the meter and skewing the measurement.