I have been suffering to start my 1951 Plymouth when the engine is hot. I have noticed the 6V ignition coil is overheated when I have this starting problem. If I wait some time, it cools down, then car starts. I have already replaced the 6V battery and the coil many times, and no solution was achieved. I changed the original location of the coil, attaching it to the fender, what reduced the overheating, but did not solve the problem completely.
Currently I use a 6V Bosch ignition coil. The temperature gauge does not need to be at maximum level to starting failure, in fact it happens at temperatures above the half of the gauge indicator. I believe the engine cooling is fine, recently the water pump was rebuilt and the radiator core changed.
I always have a spare coil inside the glove box, so I can replace the coil when the problem happens. Sometimes I just wrap the hot coil with a wet cloth, so the temperature gets down and the engine starts.
What could be the source of this problem? What is getting the coil so hot?
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