Coil frying?, Any electric gurus out there? Options

[kart54]

I posted this in the garage section and got no response so I thgought I would try here. Working on the race car last night I flipped my main power switch to test something else I was doing. After a couple of minutes I heard the oil in the coil making noise. When I jumped out of the cockpit and went to the engine compartment I found the coil was so hot it burned my fingers.
What will cause a coil to burn like that? Is it a fault within the coil itself or something external?
The coil was an MSD blaster 2 and my ignition is a Crane XR700 optical with rev limiter.
I went out today and got a new coil but I want to make sure I'm not going to fry this one as well by just installing it. Anything I should check first?
Any help greatly appreciated.
Thanks
Randy

[McMark]

I'll have to disagree and post an alternate explaination.

Your Crane must have been lined up just so to create a closed circuit. When the engine is running the crane opens and closes the ignition circuit to create the spark. Normally when the engine is stopped your crane will be in the 'open circuit' position. Occasionally the crane trigger wheel will stop with one of the windows lined up with the trigger. This will close the circuit and allow electricity to flow. So when you turn the key on, you're pumping current/electricity through the coil, basically creating a short to ground. Because the coil is the highest resistance piece in that circuit, it will build up the most heat. If you're crane trigger wheel had stopped in a different spot, you wouldn't have had a problem.

I make a habit of unplugging the coil power when I'm going to be turning the key on for long periods of time.