No power to coil

M

marilyn

New member
My 59 Galaxy will only start with a jumper from positive coil to positive battery. There is no power et coil with ignition on and jumper removed. What is the problem.
Marilyn
 
Did it just recently develop this problem? Was any work done under the dash or hood just before this happened? Does the starter solenoid click, energize the starter & turn the engine over when the key is turned? Then the engine quits running if your added jumper wire isn't there?

First thing to look at is the ballast resistor. There's a chance it may be a special piece of 'resistor wire' instead of these ceramic & metal examples. Check it for 12v ignition 'run' power on one of it's terminals (red/green wire from ign switch), and 8-ish volts on the other terminal (black wire to the coil).
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Thanks for your reply. I forgot to mention that the points and condenser were replaced with petronix module and the ballast resistor was removed. A standard 12v coil is used, not a flamethrower distributor.
Marilyn
 
Assuming the car still has the oem wiring harness under the hood...
since the ballast resistor was removed, which wire is now feeding the "+" terminal of the coil?

Is the red / green wire that was on the ballast resistor connected to something?
Do the dash gauges, Oil and Gen lights work when the key is turned on?
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So after the petronix installation it wouldn't start? Is there a full 12 volts to the wire that went into the ballast? I'd think it would still fire in the start mode. dmfsrr, doesn't the start mode power from the starter solenoid? I haven't owned a 59 car but my 59 pickup works that way. But it has the resistor wire from the switch I believe, no ceramic ballast.
I guess it would be pretty easy to just pull another hot lead from the back of the switch to the coil.
 
willowbilly3 said:
... Is there a full 12 volts to the wire that went into the ballast? I'd think it would still fire in the start mode. dmfsrr, doesn't the start mode power from the starter solenoid? I haven't owned a 59 car but my 59 pickup works that way..
....
Click to expand...
Yes, the way these cars/trucks are wired there are two sources of power to the ignition coil.
While the starter is cranking, the "I" terminal of the starter solenoid sends full 12v power thru a separate wire to the "+" terminal of the ignition coil.
When the key is released to the 'run' position, power to the ign coil comes from the "C" (coil) terminal of the key switch thru a (usually red/green) wire to the ballast resistor (or the special section of resistor wire) and from there to the "+" terminal of the ignition coil. The voltage at that end of the wire is approx 8 volts.

If an ignition coil is marked or has an 'internal resistor' it doesn't need an extra (external) resistor. If the coil is marked '12v, use external resistor' the resistor should be left in place. See the quote from Pertronix Tech Support and the comments at this link...
https://www.fordbarn.com/forum/showthread.php?t=218770

marilyn,
Will the starter turn the engine over without the extra jumper wire in place?
If the car won't start without the jumper wire to the coil in place, go back to the ignition switch looking to see where the power is, and isn't.

If the car starts but will only run with a 12v jumper wire to the coil "+" terminal, that leads me to believe the power wire from the ignition switch to the coil is either not connected correctly or the key switch may be bad.
Things to check: The "C" (coil/run) terminal on the ign switch should have 12v with the key in that position and the (red/green) wire to the ignition parts under the hood should be connected to that terminal. The other end of that wire where it was connected to the ballast resistor should have 12v on it with the key in 'run' position.
If the ign coil is marked "use external resistor" the ballast resistor should be reinstalled, with the red/green ign wire from the key switch connected to one terminal and it's other terminal has a wire to the "+" connection of the coil.
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There is no way to "talk" this thing fixed without more communication from the original poster. A test light or vom is needed. Disconnect the power wire from the coil, turn the ignition to "run" and start probing the wire back toward the switch until power is found. If there is no power at the ignition terminal and there is power at the battery terminal of the switch, the switch is most likely bad.
 
Mike V. Florida said:
Standard or auto transmission? I'm thinking maybe the neutral safety switch.
Click to expand...
If the neutral safety switch is wired correctly it's in the wire that provides power to energize the starter solenoid, not the ignition coil.

In any case, marilyn hasn't responded recently, so we have no further clues.
 
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