Anybody know where the actual ground connection is for the coil?
I get 12 volts on the positive side when I check to good ground. But on both wire terminals it fluctuates from 3 volts down to .1.
Can I reground the coil somewhere else?
Thank you in advance,
FWIW it is a 460 in a E-350 chassis for a Winnebago motor-home.
I have replaced all ignition wires, coil cap rotor. Each one seemed to fix the problem for a while. It has run fine every once in a while but then won't start.
I see the OP says he has 12 volts on the +side of the coil.
Did you mesure that, or use a test-light?
Should'nt it be more like 6.5 volts? Doesn’t the Ballast resistor drops the voltage ?<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
I checked the voltage on the + side of the coil to ground and it is 6.5 volts.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
I thought that the electronic ignition used 12 volts to the coil, so we check another vehicle with the motorcraft ignition and it was 6 volts.<o></o>
This was on a 1987 460, carbureted, MoHo. <o></o>
Rebuilt the Carb today, of course it started right up and idled for 7-8 minutes then died. Wouldn't restart, but at least it won't catch on fire now.
Took out the coil and it checked out fine.
Just looked at the Duralast/Control Module - Ignition online and for 27 bux should have just bought one. I am guessing that is the next step in the electoral system.
The coil is grounded in TWO places. The low voltage (12 volt) side grounds thru the sensor and the high voltage side grounds thru the spark plug. But if you are checking voltage with the sensor on the negative side of the coil you will get all sorts of strange readings. But your symptom of starting and running until warm and then dying is a classic bad coil problem.