for ignition wiz....
- Thread starter froggy
- Start date
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I believe the ballast resistor is for points-type ignition.
If you converted your distributor to HEI or pertronix, you can toss it
Do you still have the coil instalation instructions?
manny 72fj40
If you converted your distributor to HEI or pertronix, you can toss it
Do you still have the coil instalation instructions?
manny 72fj40
It looks like the resistor has more to do w/the ignition coil then points...maybe both?
manny 72fj40
http://www.users.bigpond.com/jack_stands/automotive_advice/ignition_system/ignition_2.html
manny 72fj40
http://www.users.bigpond.com/jack_stands/automotive_advice/ignition_system/ignition_2.html
if its points type ignition then yes you need a ballast resister or you will burn up the points real quick. they should only have about 9 volts to them, 12 will fry them. the coil steps up the voltage for the ignition the points just tell it when to fire. all the resister does is reduce 12 v to 9v. hope that helps.
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The ballast resistor also reduces voltage to the coil. OEM has a link that bypasses the resistor when starting (engaging starter feeds full 12v to coil) for a "hotter" starting spark. Once the key is at the "on" position the coil is fed through the ballast resistor, which like gunman said reduces voltage to 9v.
So yes, if you have points, you must have a ballast resistor.
So yes, if you have points, you must have a ballast resistor.
On a points type 40 there is a ballast resistor in the wiring harness. You get 12V to the coil while cranking for a hot start up spark, then 9V during running to avoid burning up your points. If you are replacing a coil same-same you can just hook it right up.
You can tell if it works if you have 12V in the start position and 9V on run. If it fires on start, but dies as soon as you release the key, then the ballast is probably toast. You can replace it with a Chrysler type ballast if you want.
You can tell if it works if you have 12V in the start position and 9V on run. If it fires on start, but dies as soon as you release the key, then the ballast is probably toast. You can replace it with a Chrysler type ballast if you want.
- Thread starter
- #8
thank! now I understand 
. . that this can't be my problem..... When my cruiser is hot (normal hot) it just won't start!!! the timing and tune up is done. I had a similar problem with a mazda and it was the coil. The more the engine was getting hot , the worst the car was going, to a point where it didn't start at all. My cruiser runs ok but if I turn it off, it won't start until it's cold??
I'm confused.....
. . that this can't be my problem..... When my cruiser is hot (normal hot) it just won't start!!! the timing and tune up is done. I had a similar problem with a mazda and it was the coil. The more the engine was getting hot , the worst the car was going, to a point where it didn't start at all. My cruiser runs ok but if I turn it off, it won't start until it's cold??I'm confused.....