Short update I received a new coil from Mitchell Motor Parts www.mmpar.com And you wouldn't believe the difference, NO hesitation what so ever! and smooth idle. For me replacing the coil made a big difference , I have a autolite replacement just remember to ask for the coil bracket if you want to install one .? ;)Thanks for all the responses Happy plymouthing DANiel

Darren
in answer to your question how long you can leave the ignition on without damaging the coil ther is no set answer to this , but i have found over the years that a couple of hours is enough depending on the age of the coil. also the points and condensor can also be damaged this way depending on wether the points are open or closed. As for the dents in the coil  i have been using a dented coil in my 54 diplomat for over 14 years with no problems . my suggestion is if in doubt get it tested ,any good auto electrician will be able to do this
Rex

Darren,
A dent in Your coil could deform the copper coil wires. With their laquer insulation skratched, they even could get permanently or interruptedly grounded. Take a new one and compare the Ohm value of both of the various terminal combinations. You need a good ohm meter, because of some very short windings reading only a few ohms.
1946 - 1953 Service manual says: (for negative grounded car)
Connect Am meter between neg coil primary  terminal           and    neg battery post
Connect Volt meter between same terminal                         and    ground
Connect coil case, pos coil primary terminal, pos battery post   and    ground
Allow 5 minutes to warm up, Ammeter shoul read 5.0 A and Voltmeter 6.3 V

High tension secondary circuit may be tested by removing the high tension lead from the distributor cap and halding the end 1/4 inch from the cylinder head and turn ign switch. If spark jumps the gap, coil should be satifactory.

For high speed miss, coil should be tested on a coil tester.

Always make a test cool and one hot.

Be aware not to get too near to the spark gap - it gives stron shocks to You!

Greetings! Go

I am replacing my orginal coil this week ,  Somewhere in time it once got a dent on the side ,I was wondering if  any one would know if a slight hesitation  only when hot  , could that  be a sign of a bad coil?
Also I was wondering how long if one left a key on the on position with out the engine running it would take to burn out a COIL or if it anyone would know if it would not hurt or weaken the COIL?
and if it would or wouldn't could u burn out the condensor or burn out points ?

This is the only part I did not replace with either NOS or NORS. ie New Gas tank  fuel pump Carb wires dist cap plugs vacum advance  autolite breaker point unit with condensor.
Thanks for the info, DANiel