Check that you have power to the coil when the ignition is switched on, and that its there when engine is cranking. You can do this with a bulb of the correct voltage, connect one side to a good earth, the other to the desired test point. You can also try disconnecting the centre lead from the distributor and taping its bare end about 1/2inch from a suitable clean earth such as cylinder block or head. Remove distributor cap, turn engine until points are closed, switch on the ignition, and using a small insulated screwdriver flick the points open. You should get a small arc at the points and also a spark at the coil lead. This is the basic way of checking both LT. and HT. systems. I would guess that you have a broken lead inside the insulation either in the switch to coil or coil to dist. leads.
Hope this may be helpfull. You can carry out the above checks quicker than it takes to explain!
Mr. Toad
September 2008
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