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Bench testing a coil

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TodE

Jedi Hopeful
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Is there some way to bench test a coil in or out of the car?
I am restoring a BN1.(Positive ground) Motor and transmission back in car. New wiring harness. Car started up 2 times, car did not run great (timing off. Both points gap and timing.) Adjusted points gap. Tried to restart, car would crank, but would not start. Car getting fuel, no spark at points or spark plugs while cranking????? Tried with starting fluid would crank, but would not even try to start.
I have 12 volts to the coil, but nothing on the other side. CB terminal side, but not SW side when I crank???
I am guessing coil, but why did it start before and now won't?? What am I missing?? Coil wire is on coil and rotor cap.

Thank you,
Tod
 
I have 12 volts to the coil, but nothing on the other side. CB terminal side.

Yes the coil or the condenser could be defective but it just may be the point terminal inside the dizzy was grounded inadvertently when the new points were installed.

IN The Car.:
With the ignition on and the volt meter attached to the CB terminal you should see the voltmeter follow the points open =12V closed 0Vwhile cranking.

Ohn Meter test:
Wuth ignition off.dusconnect the CB lead from the coil conect the meter between this lead and groud . Set the scale to 10,000 ohm or more now crank engine with button on solenoid.
! meter shows a constant short: Problem in dizzy
2 Meter follows points: points open = 10K Ohms
Points closed = 0 Ohms.

If $ 2 SUSTITUTE A KNOWN GOOD COIL.---kEOKE
 
Keoke,

Thank you for your input! As always, you are very helpful. I will write your procedures down for next time.
I solved the problem, but not sure I understand whats happening???

I replaced coil with a used coil. Turned the master switch on, car started right up!
Shut car off, turned the master switch off. (Went about doing some other tasks.)
Then went to start car again, it would crank, but not start! Then I remembered I had turned the master switch off! Turned switch on, car started fine!!

SO.......
As I stated I am running positive ground. So I have pos wire from battery to one side of switch, the other side of switch going to ground strap, going to frame. Goofy little wire anti theft wire under screw, but I did not cut the insulation back. (Just appears to be hooked up for looks.)
The switch is a new reproduction.

A switch is a switch. It isolates one side to the other side, Right? It should not matter which side is hooked up to the pos side of the battery?? Right?

To recap: Switch "ON" car starts fine. Switch "OFF" car cranks, but will not start. Why am I getting power to starter with the master switch "OFF"??

I am also using two 6 volt batteries with the neg wire from battery going to solenoid switch under hood. Reduction gear starter.

Thank you for any help!
 
TodE said:
Keoke,

...
A switch is a switch. It isolates one side to the other side, Right? It should not matter which side is hooked up to the pos side of the battery?? Right?

To recap: Switch "ON" car starts fine. Switch "OFF" car cranks, but will not start. Why am I getting power to starter with the master switch "OFF"??
Click to expand...

This isn't just 'a switch.' It both isolates the battery and shorts or opens a circuit to ground for the coil primary. In the 'off' position the 'goofy little wire' grounds the coil primary so you won't get spark, in the 'on' position the circuit to the coil primary is open so you'll get spark.

If the engine cranks in both positions the switch is malfunctioning; probably leaking enough to allow the starter to turn (esp. is it's a modern, hi-torque or reduction starter).
 
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