Help no spark to distributor

Well it's probably not IN the ignition system

Run two tests.

Clip your voltmeter to the "key" side of the ballast, or if you cannot identify which side, hook to the blue alternator field wire (70/later) or to the regulator IGN terminal (69/ earlier) and the other probe to battery POSITIVE

Turn the key to "run" and carefully measure voltage, which should be VERY low reading, not over .2--.3v (3 tenths of one volt)

If this is higher, it shows you have a harness drop. You can provide a "quick test" by using a clip lead from the coil + terminal to a battery source, like the start relay stud, and see if it runs. Do not leave this hooked up for long

A second test you should make is to clip your meter to coil+ and to battery + Crank the engine USING THE KEY. You should not read more than .4V or so at the most, less is better.

Next clip your meter from coil+ to ground, and crank the engine USING THE KEY. You should see AT LEAST 10.5V during cranking.

Check for spark right at the coil tower using a grounded probe, which will eliminate bad coil wires or problems in the distributor. It is important to do this one of two ways:

Either do so USING THE KEY

or use the clip lead above, jumpering from coil + to battery, and then you can do so by jumpering the start relay.


BEST way to do this is to "rig" a spark gap, either buy a commercial spark tester or use an old plug, and use a piece of solid core wire and get the "test" plug up by the cowl so you can see it while twisting the key. Open the gap way out, and ground the plug.