Bill:
Although this is probably not your problem, there is no need to use a
screwdriver to open the points. Using the screwdriver may just ground out the
points, and consequently you'll get no spark. You can open the points with a
finger nail as the voltage at the points is only twelve volts and it won't "fry
you."
Going on to the problem:
Did you determine that the coil is getting power? Turn the key on and check with
a VOM meter to see if there is 12 volts between the positive terminal of the
coil and ground. If you don't have a VOM meter, use a 12V test lamp. Just
disconnet the wire at the positive terminal of the coil, grasp the terminal
agains the bulbs copper case and touch the center base terminal of the bulb to a
clean ground with the ignition switch on. If it lights, you've got power to the
coil, then problem is in the coil, distributor, or points. You can also test
after the coil, and at the points, althought the bulb may be a bit dim because
of the coil consuming power.
If there is no power, prepare a jumper wire with small aligator clips on each
end and wire directly from the battery and the positive terminal of the coil.
Flick the points again to check for spark. On my MGA, you can quite often see
and hear the points spark when you open them with the finger. If you now have
power at the points, then there are problems with the ignition switch, or the
wiring to/from the ignition switch.
The latest wiring diagram for a MGB I have is 1972. Does this car have a
ballast resitor in the ignition start circuit?
Blake
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