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TR6 What's for dinner? Fried Coil???

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2wrench

2wrench

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Hello, everyone. Car is deciding to just shut down. Idles....stops. I start it....idles, might even run a while....stops. Pushed it home
on the last run.

Found no spark past the coil. Went to remove negative wire from coil.....saw sparks.....bolted it back down. Car started and ran, then stopped.

Replaced old coil with new coil. 12 Volt 1.5 ohm for my ballasted setup.

Car started great. Thought I was done. Idled in garage for five minutes. Shut down. Immediate startup. Idles....shut down.

HISTORY COULD BE OF VALUE: Recently installed HVDA transmission. Grabbed one of the green "power" wires to the old overdrive
and hooked it to the backup lights. After driving a couple hundred miles, started having this car shutting down, especially at idle, but
then started coughing while driving until it decided to quit. Car has been sitting until this afternoon when I replaced the coil.

I don't think I properly taped off the green "power" wires and I wonder if they could be causing a short to the coil. Do you think I could
have other issues with regard to points, cap, rotor? Timing? Timing could be in there. I do remember the car coughed while
accelerating uphill grade in 5th gear.

Any thoughts?

Thanks.
 
My guess, you've got a wiring problem, but not necessarily the green wire touching ground. If it did touch, that should blow the fuse, but the coil would still get power.

I would probably try temporarily connecting a test light from the hot side of the coil to ground; and watch what it does when the engine dies. If it goes out, you know you're not getting power to the coil sometimes.

If you are still running points, try cleaning them with solvent. I've been having somewhat similar problems with my TR3, which I think was caused by over-enthusiastic greasing of the points pivot last time. It only takes a tiny speck of grease or oil to block conduction at the points, which may clear itself given time. It would get coughing fits, then clear up and run for anywhere from a few seconds to a few days, then do it again. After cleaning both the pivot and the contacts, it's been running fine for several weeks.
 
How about the ballasted setup. Run a wire from the positive side of the battery to the hot side of the coil. Assuming it's negative ground. Start and go on a test drive. That's how I found that my ballast resister was bade in my Volvo may decades ago.
 
For years I've used a small dab of white lube on the distributor shaft and never had any fly off or cause trouble. Wheel bearing grease would probably be even better.
 
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