my battery was dead, so i swapped in a red top optima. this battery was the one it called for at advance auto but its a LOT more cranking amps. i proceed to install my new flame thrower coil and run a new wire from key switch to the positive side of the coil so i had full voltage. new set of autolite 45 plugs gapped to 40.

problem:
no matter how long i hold the key over, it will crank and crank and crank and NOT fire... untill i let off the key and then it will fire. i can crank it for 2 seconds or 5 and it will not fire UNTILL i let off the key.

heres my ideas:

1. battery is cranking faster then the motor is turning allowing it not to fire untill the cranking slows down
2. something to do with the key switch. there is a bolt type on the back of the key switch, loosen the nut, slid my new wire on, tighten it up, ran that through the firewall to the + on the coil.



ideas?

 

for 1965 car:

1) No. I'm not sure that really makes sense. The starter will crank the engine at a max. speed. Giving it full battery voltage is a good thing, and it should have it to begin with.

2) The coil gets 12v from the ignition switch. The negative side is your 'control' side, used with points or a module. Then the large center wire (high voltage) goes to the top of the cap for the plugs.

I would verify that the plugs are getting spark and that the ignition timing is correct.

 

what you have is a typical problem when coils only get 8V during cranking. there's a wire going from the selonoid to coil+ to give your coil 12V during crank to fire up. What I don't get is that you have this problem even with a new wire (no resistor) routed to coil+ (from ignition switch).

to troubleshoot, just add a new cable from th 'I' terminal of the selonoid (usually the right one of the two in the middle) to coil+ and then try again.
what this does is when your selonoid is getting 12V (when you turn the key to start) it will feed 12V directly from battery to your coil.

Try that and let us know how you get on

Kalli

 

On top of what's already been said, check to see if you even have voltage during crank. I'm betting your 12v with the key on goes away during cranking (lack of the I terminal output as kalli stated). 12v during crank and around 8v running is normal.

 

what kalli said. i had a 1955 f100 that started that way, it only had a 1 wire starter solenoid.

 

figured it out, the wire i ran connected to the acc. part of the key switch. during cranking there was no power untill it kicked back into the acc.


fixed lol

 

lol. i would never have thought of that as ACC is to left of off. I never had my key in that position. not once in 3 years.