My 54 chevy is burning up coils in about a three month time span. Its a 235 straight six converted to a 12volt system with a single wire alternator. After the second one I put a resister in line and figured problem solved but to my dismay I fond myself broken down once more. Any suggestions
6 volt or 12 volt coils? When you change to a 12 V charging system you need to change to a 12 V coil too.
Make sure the "hot" wire from the ignition switch goes to the + terminal, and the dizzy wire to the - . What value of resistor are you using, where did you get it?
Is there a problem with the iginition switch...If let on it can burn up a coil pretty fast...make sure the key is always off. Just from experience
It is to my understanding that a 12 volt coil actually only runs on 8 volts, or so I've been told. Did you check the voltage after the resistor?
I'm running a 250 I6 in my 52...put a Pertronix in 11 years ago and a brand new Blaster coil...the coil lasted about 1 1/2 years at which time I went out to the 57 IHC pickup in my back yard and took the Delco oil filled coil off and put it on to get going....it's still on there....rusty crusty, not chrome or go fast HOT RED ...BUT..it hasn't let me down. I would guess that some of these new parts are ****!...just a guess, tho'...
Coils die from excessive current. Excessive current comes from incorrect primary resistance. (lower than spec) Your system needs approx 3-4 ohms resistance in the primary, any less and you will have pattern failure based on too high of current. Options are use a 1.5 ohm ballast and a 1.5 ohm coil or use a single Bosch blue ( 4 ohm coil ) with no ballast. We stock the 4 ohm coils if you have a problem finding one....... Glad to help......
Two thoughts. How is your coil mounted? is it vertical or laid down horizontally? I always wondered why they sold oil filled coils or ceramic filled heavy duty stuff and what the difference was. I got my answer on the side of Highway 8 at 11:00 one Sunday night, fifty miles from anywhere! Oil filled coils are made to sit up right in their bracket, keeping the windings submerged and cooled. Lay that same coil down, and the windings along the top of the coil are now exposed and not cooled, leading to overheating and failure. The ceramic or epoxy versions are made so that they can be mounted in any configuration and not have any of their windings exposed. Only took a four hundred and fifty dollar tow bill, a medium sized engine fire, and a call to MSD to find that out. The other thought I mentioned - if you want to get rid of that damn ballast resister, (and you should!) try a VW style Bosch blue coil. Heavy duty, and internally resisted, it'll last a lifetime.
and there is no such thing as too much ground. import tuners are showing 3-5 hp at the wheel from adding several extra ground straps.
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