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12volt or 6 volt coil How do I tell

T

thelasthour

Member
"Before I deal with the headac

"Before I deal with the headache of running a bypass wire from my starter to my coil and skip my ballast resistor on startup, I'm wondering if I have a 12 volt coil to begin with. The coil is painted so I don't see the "sticker", but the engine was a new "powerpack" in 2006 with ignition connected. mallory unilite, no points. Wouldn't it be logical that the factory set it up with a 12 volt coil? The wiring diagram called for a ballast resistor,so that is how the shop wired it. They did not however, run the bypass. How can i test my coil and see if I can eliminate the ballast all together? It has been running for 2 years with the ballast in place BTW. Now it doesn't want to start without the bypass. Everything that I've read on here makes me believe the 6 volt coil is a dinasour and wouldn't be on a 2006 motor in the first place.
Steve"
 
"I'd be more inclined to t

"I'd be more inclined to think the question is builtin vs external resistor required.

I'd agree, 6 volt coils are rare today and the likelihood of having one is low and having a 6 volt coil run on a 12 volt system for two+ years is really close to impossible.

How can you tell - I'd measure the current draw the coil creates and contact the 'factory' and see if they can provide you a range of values. An alternative is to guess it is a mallory coil (to match the unilite) and see what range they provide."
 
"Can I use an OHM meter and se

"Can I use an OHM meter and see measure the posts on the coil and look for "resistance" that is similar to the "resistance" from the ballast resistor? If it shows "resistance" then I can assume that I have a 12 volt coil, and ditch my ballast?
Steve"
 
"they will all have resistance

"they will all have resistance. You can measure it be you need an accurate low value ohm meter to get accurate measurements (that's why I suggested measuring the current). Going on mmemory, a nominal coil primary is ~1.0-2.0 ohms and the built-in resistor almosts doubles the total resistance. (eg,bare coil=1 + internal resistor=1 so total ~2.0 ohms.) values could be off a little but are all in the single digit range; a few are less than 1.0 ohm.

I'd check their www page for a phone number. A local dealer/distributor should have the info, too."
 
"If it's a ballast resisto

"If it's a ballast resistor setup, the coil is around 9 volts, not 6.

Jegs (on-line) sells a nice, high performance, 12 volt coil for under 30 bucks. Why not buy one and toss out the ballast resistor? Done!

Jeff"
 
"So I contacted Crusader and t

"So I contacted Crusader and they told me the ballast was required to protect the distributor module. It is a 12 volt coil. He was unclear whether or not a coil with "internal resistor" would work. Does that mean that I have a 12 volt coil WITHOUT an internal resistor thus requiring the external ballast. So I buy Jeff's coil and I'm good, or then do I burn up my mallory module??? He also said the bypass was not necessary, just change the platinum plugs to mr43lts and it would start easier.
Steve"
 
"The Crusader guy was telling

"The Crusader guy was telling you you have a 12VDC coil W/O an internal resistor. The resistor's purpose is to limit current flow in the circuit.

On the other coil, maybe be OK...best to check with Mallory and see what their (your) module requires and decide based on that. I checked a couple unilite sheets and they ALL said use a ballast resistor - check their www site with your part number.

On the plugs, they are likely to have more insight. Only costs a few bucks and the time. Couldn't hurt. I wouldn't think adding the bypass feed would be a hard job but I haven't seen your engine room."
 
"It's surprising how confu

"It's surprising how confused some people get on this ballast resistor issue. To wit:

If the coil is designed for 12 volts then you don't need the resistor (and the module could care less.) But if the coil is an "external resistor required" (9 volt) coil, you need the ballast resistor or the coil and module will see way too much current and burn up.

Jeff"
 
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