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| | | | Joined: Sep 2003 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Sep 2003 Posts: 50 | Hillbillytim is using a 12 volt battery to power his 6 V coil ignition with a ballast resistor inline to the coil. I have a 6 V electronic ign. module and want to convert the entire truck up to 12 volts. I've got a ballast resistor to install inline from the switch to the coil (still 6 volt coil) and would like to keep my module as it is for cost consideration. It's wired to the positive side of the coil directly downstream from the resistor. Will this work or will I fry something or stall out? And another consideration...this is a floor start 54 half ton. There is no accomodation in the ignition switch (the sprung type switches have that) for extra 12 volt boost bypass to the coil when starting. Will that be a problem? | | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Why not just leave it 6v? 
Save a life, adopt a senior shelter pet.
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| | | | | Joined: Nov 2007 Posts: 190 Shop Shark | | Shop Shark Joined: Nov 2007 Posts: 190 | What are you using to recharge the 12 volt. battery? You will need to upgrade your original generator and voltage regulator. You can IM me on this site for more info on this and help.
Thanks,
Ken
| | | | | Joined: Jul 2007 Posts: 461 Shop Shark | | Shop Shark Joined: Jul 2007 Posts: 461 | I don't think you need the ballast resistor with the electronic ignition system, even though you are using the 6v coil. The 6 and 12 volt coils have about the same primary resistance. Usually 12-volt electronic ignition systems don't use a ballast resistor in the coil circuit, but some use one in the control circuit. It depends on who made the system you have. You will likely get a weak spark if you leave the ballast resistor in the coil circuit with the electronic setup. Go by the manufacturer's instructions for the hook-up.
The reason for the ballast resistor in the 12-volt contact systems is to protect the points. I'm with Tiny- why not leave the truck 6-volts?
Harvester | | | | | Joined: Sep 2003 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Sep 2003 Posts: 50 | Thanks for the responses, sorry I've taken so long to get back. Reasons for 12V upgrade: I could dispense with the 9 inch flywheel I have been using since I got the truck (someone had put in a 1942 216 flywheel with a matching 6 volt starter). We put in a fresh rebuilt 235 1956 motor during the 12V upgrade and the core we found came with a 10 inch flywheel but it was for 12V (168 or so teeth versus the 139 or so of the 6V). Finding a 10 inch 54 6V flywheel just seemed like more trouble than I needed. Also there were still charging issues with the 6V despite all new or rebuilt charging and starting system and despite too, having ground strapped everything but my mother when she went for a ride in it...and still the battery would get weak and headlights dim.
Here's the exciting part: my buddy and I decided to store the 6V distributor with the 6V electronic ign module for a rainy day, and re-use points and cond. with the 6V coil and a ballast resistor from a 79 to 86 Dodge product (part# AL125DCS). I thought I should get a 12V universal coil (for use with external resistor) to be on the safe side. When I hooked up the 12V coil, NOTHING. NADA. Wouldn't run at all. When I re-hooked up the 6V coil and 12V resistor in the new 12V system ... MAGIC! It ran like a champ. We took the truck on a 200 mile break in run and had zero problems with the cheap Wal-Mart 12V battery, Dodge 12V ballast resistor/6V coil and 6V points/condensor arrangement.
There was one problem: we hit the mountains in a blizzard and still had the 6V blower motor in the heater...
scraping ice off the INSIDE of a windshield in unpleasant.
One more thing, a voltage meter across the resistor to ground when engine running shows 12 volts out to coil. So the Dodge resistor is only dropping the volts by about 2. Weird. But I cannot argue with success. I have another 6V coil in the event this one takes a dump. So far it neither heats up unusually nor stalls out.
...BTW, 12V halogen headlights are excellent for brightness! We'll probably not be using 6 volt again. If anybody needs a slightly used rebuilt 9 inch 6 volt pressure plate and flywheel, recently rebuilt generator and starter and new regulator with probably less than 5,000 miles on them, let me know.
I have to figure out a voltage drop transistor circuit for the original 6 volt radio. Resistors don't really work. | | |
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