The Ford Barn

richard instness · 07-01-2019, 02:51 PM

Hi,
I have a model A that the coil seems to be getting hot on. The car runs fine, but after driving for about 30 minutes the coil is pretty hot. Hot enough to only keep your hand on it for a short time. The car is 12v negative ground. I have tried 3 different 12v coils running both internally resited and a coil with a external resister. The first 2 coils showed a resistance of 1.4-1.5 on the ohm meter. The coil that is currently on the car is a Bosch 12 volt blue coil. This coil shows a resistance of 3 .0 on the ohm meter. Currently the amp meter shows a charge of about 10amps while driving. Any ideas what might be causing the coil to heat up?

07-01-2019, 02:51 PM	#1
richard instness Junior Member Join Date: Feb 2019 Posts: 2	Cause of hot ignition coil? Hi, I have a model A that the coil seems to be getting hot on. The car runs fine, but after driving for about 30 minutes the coil is pretty hot. Hot enough to only keep your hand on it for a short time. The car is 12v negative ground. I have tried 3 different 12v coils running both internally resited and a coil with a external resister. The first 2 coils showed a resistance of 1.4-1.5 on the ohm meter. The coil that is currently on the car is a Bosch 12 volt blue coil. This coil shows a resistance of 3 .0 on the ohm meter. Currently the amp meter shows a charge of about 10amps while driving. Any ideas what might be causing the coil to heat up?