The Stovebolt Site Forums The Shop Area The Electrical Bay Coil voltage

59 apache, 235ci, 12v. orig dist, stock setup... While running I have 15 volts out of generator to ballast resistor, 11 volts from resistor to + side of coil. How many volts should I have from - side of coil to distributor?
I'm reading about 8.5 volts from - side of coil to distributor with a digital multimeter. Doesn't seem right to me.
Darren

a stock setup doesn't have the generator output to the ballast resistor, the voltage at the resistor should be battery voltage [via the ignition sw], and the resistor should drop that to around 8V .... sounds like you may have an internally resisted coil that doesn't require a ballast resistor

Bill

The coil says resistor required. I have rewired the entire truck with new stock type harness. Maybe I have some wires wrong? I have 14-15v at top of resistor when running and 11v at bottom of resistor and at + side of coil. The 8v at - side of coil is what confused me, I thought the coil was supposed to boost voltage.
My main issue is the truck stumbles and wants to die when coming to a stop after running at hwy speeds. I have changed fuel pump, fuel lines, rebuilt carb again, even replaced the carb, Still same problem. Truck has been back on the road for a year now after resto. Gas tank has been flushed, cleaned, sealed, new fuel pickup and lines.

The voltmeter is reading an average of the "points open" voltage (charging system voltage) and the "points closed" voltage which should be close to zero. Tha 8 volt reading sounds about right if the point gap is set properly.

The coil boosts the voltage at the center tower, the one that goes to the middle of the distributor cap. There's absolutely nothing wrong with your ignition system- - - -if the engine runs, don't over-think it! Drop me an email if you want to discuss the operation of the coil without getting a lot of conflicting opinions- - - -I've been teaching ignition system theory successfully for over 30 years to a bunch of high school students the counselors think are too dumb to be in regular education classes like "music appreciation"!
Jerry

Is there any chance that your gas cap is not venting properly?

I have ran it without the gas cap, still same problem. I'm thinking maybe I need to pull out the pickup tube/sending unit and have a look at it. It's a new aftermarket unit probably made in China.

Update! Problem solved! Valves were too tight! DUH! I found out you can't adjust the valves on these old 6's like you do a SBC V8! Lesson learned, valves must be adjusted with engine warmed up.
Thanks all for your help!
Darren