Eliminating fuel as the potential problem is progress.
I don't understand the statement I took out the HT lead from the coil and put the test light in the coil. Turned the engine over on starter but no light.
If you removed the HT lead and then inserted a 12 v test light into the HT socket, that is not going to work. The simplest way to test for electrical continuity in the primary circuit of the ignition coil is to disconnect the wire from the negative terminal of the ignition coil, then turn the ignition switch to the run position and then check for voltage between the negative terminal of the ignition coil and chassis ground. If the primary circuit (including the coil primary winding and ignition switch) is OK, then you should measure 12 volts. If you don't measure 12 volts, then one of the following has occurred
- the coil primary winding has failed open circuit
- the + power supply the coil has failed (which could include the ignition switch)
If the check at the negative terminal of the coil gives you 12 volts, that tells you that the primary circuit is OK. It is still possible that the secondary circuit of the coil has failed. Clamping the inductive pick up of the timing light on the coil HT lead will allow you to check for spark voltage (it will give you 4x too many flashes to do an actual timing check). If the timing light strobes when triggering from the coil HV terminal then the secondary wingding is OK.
If all of the above leads to indeterminate results, I suggest the ultimate hot wire test.
-Find a new conventional ignition coil.
- Securely tape the new ignition coil to the side of the existing ignition coil.
- Transfer the HT spark lead and the wire to the negative terminal of the coil from the existing coil to the new coil.
- Run a length of wire from the positive terminal of the battery (or any convenient unfused 12 v source) to the positive terminal of the new ignition coil. This wire needs a switch in it - you will need the switch to turn the engine off once it starts and to prevent you from draining the battery through the coil circuit when engine is not running.
You have now completely eliminated the existing ignition coil and all of the cars internal 12 volt wiring as a factor in the ignition failure problem. If the engine runs without fault with this temporary coil arrangement you know that the problem is the existing coil or 12 v supply to the coil. If the problem remains with this hot wired coil, you know that the ignition problem is in the distributor or with the high voltage wiring / spark plug cap.
I must admit this has one of the most impenetrable ignition failures that I have seen on what is a fundamentally simple ignition system.
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