That sounds like the early model Pertronix I had on my '67, i.e. the magnet ring which rotates above the main unit mounted on the breaker plate.
My instructions said the gap between the ring and the unit should be no less than .010 and no more than .040 (If I remember correctly). If the gap is more than .100 installed, the engine will miss or not fire at all.
Prior to installing the unit, did you check for excess gap at the gear end of the shaft? The kit should have included some shims to eliminate that gap. Add the washers to get the up-down shaft movement down to about .020.
To test the unit:
1. Remove the coil wire from the distributor and ground it to the engine.
2. With a multimeter set to 50 volts DC, put the red probe on the negative coil terminal and the black probe to ground.
3. Have someone crank the engine.
4. If the meter shows:
A constant reading of between 1 and 3 volts, the Pertronix unit is bad.
A fluctuation of between 1.5 and 12 volts, the unit is ok.
Hope this helps.
My instructions said the gap between the ring and the unit should be no less than .010 and no more than .040 (If I remember correctly). If the gap is more than .100 installed, the engine will miss or not fire at all.
Prior to installing the unit, did you check for excess gap at the gear end of the shaft? The kit should have included some shims to eliminate that gap. Add the washers to get the up-down shaft movement down to about .020.
To test the unit:
1. Remove the coil wire from the distributor and ground it to the engine.
2. With a multimeter set to 50 volts DC, put the red probe on the negative coil terminal and the black probe to ground.
3. Have someone crank the engine.
4. If the meter shows:
A constant reading of between 1 and 3 volts, the Pertronix unit is bad.
A fluctuation of between 1.5 and 12 volts, the unit is ok.
Hope this helps.