65 satellite killing coils.

[65PlymSatellite]

Hello all, was hoping someone had run into the same issue as me, or can help diagnose. My 65 satellite with 273 and points distributor keeps burning up coils. It starts stumbling and sounds like it wants to die out when driving at normal temp. I replaced the coil, ballast resistor, and voltage regulator thinking it was one of those. When running at idle, I found that the positive side of the coil reads 14v. I drove around the block, less than 2 miles, and when I came back the coil was so hot I couldn’t keep my hand on it more than 3-4 seconds. It burned up an MSD blaster and I got a Napa replacement, and it gets just as hot. New and old ballast read about same voltage on input and output, as I tested voltage with key on with both.

Anybody run into this issue?

 

[Bird 426]

I am not an electronic guy, but I thought that the ballast resister cut the voltage down, like almost in half?

 

[65PlymSatellite]

I am not an electronic guy, but I thought that the ballast resister cut the voltage down, like almost in half?

That’s why I’m confused. From what I’ve read, the ballast resistor should reduce voltage and feed 8 to 9v volts to the coil. I tested both my ballasts and get same results.

 

[RemCharger]

I am not an electronic guy, but I thought that the ballast resister cut the voltage down, like almost in half?

Exactly.
Some how the coil is hot wired to full voltage.

 

[Beekeeper]

Sounds like the ballast wiring has been bypassed somehow

 

[AR67GTX]

The ballast resister and coil should be balanced together to work properly but I'm not sure if that is to primarily to protect the points, or both coil and points. Do you know the specs on the coils you are running and the resistance of the ballast resister? I thought 8-9 volts was more typical of the distributor side of the resister, but I don’t ever remember testing for it.

 

[65PlymSatellite]

Exactly.
Some how the coil is hot wired to full voltage.

Sounds like the ballast wiring has been bypassed somehow

That’s what it sounds like to me too. Only thing is that the only people that work on this car is my dad and I. We haven’t messed with the wiring, and it was working normally up until recently.

 

[65PlymSatellite]

The ballast resister and coil should be balanced together to work properly but I'm not sure if that is to primarily to protect the points, or both coil and points. Do you know the specs on the coils you are running and the resistance of the ballast resister? I thought 8-9 volts was more typical of the distributor side of the resister, but I don’t ever remember testing for it.

I bought an MSD coil and ballast set like 3 years ago. Have been on the car since then with no issue until recently. When the coil burned up, I bought a replacement MSD coil (same as the one that came in the kit with the ballast resistor) and that one burned up too. Bought a NAPA coil and ran it today, but the coil’s just too hot.

 

[RemCharger]

New and old ballast read about same voltage on input and output, as I tested voltage with key on with both.

Just for fun, I'd try starting the car, and then disconnecting the ballast.
It should continue to run...

Edit;
It must be grabbing B+ from the brown wire if everything Is truly virgin

 

[Don Frelier]

Hello all, was hoping someone had run into the same issue as me, or can help diagnose. My 65 satellite with 273 and points distributor keeps burning up coils. It starts stumbling and sounds like it wants to die out when driving at normal temp. I replaced the coil, ballast resistor, and voltage regulator thinking it was one of those. When running at idle, I found that the positive side of the coil reads 14v. I drove around the block, less than 2 miles, and when I came back the coil was so hot I couldn’t keep my hand on it more than 3-4 seconds. It burned up an MSD blaster and I got a Napa replacement, and it gets just as hot. New and old ballast read about same voltage on input and output, as I tested voltage with key on with both.

Anybody run into this issue?

Key on with points open both sides of the ballast will read the same since you have no current so no voltage drop either.

Was it key on and not running?
Then you should see 12.8 at most.

 

[65PlymSatellite]

I experienced the whole ballast and coil scenario like 5 years ago when my dad and I were converting his 1950 Chevy from 6 to 12v. It would run fine, but once it got hot, it would run bad and even turn off and wouldn’t run again until it was cold. I realized we were cooking the coil and points. The old 6v system ran battery voltage straight to the coil with no issue. With 12 v , you need some kind of “reducer” so you’re not frying points and coil. The coil on the Chevy would get hot and we realized what was going on. We took off the coil and ballast from my Satellite and used it on the Chevy for experimental purposes and it ran great. The coil would warm up, but never get hot. We ended up using a coil with an internal resistor on his Chevy.

 

[65PlymSatellite]

Just for fun, I'd try starting the car, and then disconnecting the ballast.
It should continue to run...

I didn’t think of that, good idea.

 

[turbine68rt]

What is the dwell set at currently?

 

[65PlymSatellite]

Key on with points open both sides of the ballast will read the same since you have no current so no voltage drop either.

Was it key on and not running?
Then you should see 12.8 at most.

Car running read 13-14v at coil and output side of ballast.

 

[65PlymSatellite]

What is the dwell set at currently?

I don’t remember the specs at the moment. I bought an old Sears dwell meter and set the points to spec, just don’t remember what that spec is right now. Maybe I did it wrong? Maybe that dwell meter reads wrong? Could incorrect dwell cause too much voltage to be pulled to the coil?

 

[Bird 426]

Dwell is 30. Gap, roughly the thickness of the cardboard box the points and condenser come in. Starting the car the coil gets full voltage, run position is through the ballast. All coils are not the same. Possible problem at the firewall connector? Or rub through on wiring and always getting 12 volts? Ign switch? I am rambling, again, I am not good at electrical!
Sorry I can't help you.

 

[RemCharger]

Just for fun, I'd try starting the car, and then disconnecting the ballast.
It should continue to run...

Edit;
It must be grabbing B+ from the brown wire if everything Is truly virgin

 

[65PlymSatellite]

Dwell is 30. Gap, roughly the thickness of the cardboard box the points and condenser come in. Starting the car the coil gets full voltage, run position is through the ballast. All coils are not the same. Possible problem at the firewall connector? Or rub through on wiring and always getting 12 volts? Ign switch? I am rambling, again, I am not good at electrical!
Sorry I can't help you.

I heard ignition switches can cause such problems when failing, I just don’t understand why or how.

 

[twecomm]

In the "start" position, the ignition switch electrically bypasses the ballast resistor applying full battery voltage to the coil yielding a hotter more intense spark to get engine started. When in the "run" position, the ballast resistor is electrically in series with the coil reducing the voltage applied to the coil. If you are seeing full battery voltage on both sides of the ballast resistor in the "run" position you likely have a problem with your ignition switch which may be why you are having coil issues.

 

[Don Frelier]

Or somehow the start and run wires are swapped?