How to test coil?

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jammac

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I connected my elec ignition up the wrong way round to the coil which promptly smoked a lot and melted. Fitted my points back on and now nothing so I guess my coil is knackered too? Expensive mistake

How can I test if my coil has had it or not using a multimeter? Or am I just looking for a spark coming from the HT lead that joins to the dizzy cap?
 
To check the coil remove the ht lead from the coil to the centre of the distributor cap, switch on the ignition, hold the end of the lead with insulated pliers about 1/2 inch from the engine block and turn the engine over. There should be a spark, if not, then check the voltage at the +ve terminal (terminal 15), it should be at least 9V.
If this voltage is higher, check the voltage to earth at terminal 1 (coil connection). This should be 0V when the points are closed, and a voltage will be present when the points are open. If there is no reading when the points are open, the coil is open circuit and must be replaced.
Remove all of the wires from the coil terminals (remembering where they go) and using an ohmmeter attach the meter leads to terminal 1 and terminal 15 on the coil. You should get a reading of between 3 and 4.5 ohms, which is the coil resistance. A faulty coil will show a higher reading.

Next connect a lead from the meter to the centre ht connection and the other lead to either one of terminals 1 or 15. The reading should be around 9,500-10,000 ohms. It may be less but shouldn't be anywhere near 11,000 ohms. If you have no reading at all, the coil is faulty.
 
Bugger I went straight for the resistance checks as I haven't got an assistant I got 4.5ohms between 1 &15 but between the HT and either terminal it is open circuit. New coil it is cheers dude
 

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