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jsfbond

jsfbond

Jedi Warrior
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Hey; really, what terminal do I feed on the coil for power?
and how do I test the coil to see if its working?
 
Your GT6 is negative ground. Battery power gets connected to the + (plus) terminal. The - (neg.) terminal gets connected to the distributor.
 
jsfbond said:
and how do I test the coil to see if its working?
Click to expand...

The easy way is to pull the coil wire from the distributor, grab the metal end of the wire and have someone crank the motor over. The harder you hit the opposite wall in the garage will determine how good the coil is... :laugh: <span style="font-weight: bold">Seriously, don't do that unless you like 20,000 volts coursing through your body. </span>

But, you can use the same procedure and, with insulated pliers or something, holding the insulated section of the wire, place it close (1/8" or so) from the block and have someone crank the car over. Or, you could do the same thing with one of the spark plug wires with a plug attached and grounded to the block so you can see the spark. There should be a good, visible spark jumping the gap.

One other method is with an ohm meter. For a non-ballasted ignition system, coil primary resistance should be about 3.2 ohms. A high energy coil may have slightly lower primary resistance. A coil for use with a ballasted type ignition system (probably what you have) will have about half as much primary resistance, around 1.6 ohms. Resistance for the secondary winding will be very high, something like 10,000 ohms. Check that circuit resistance between the HT output (the fat middle terminal) and one of the primary input terminals.

The primary winding is measured between the two small posts of the coil. Do all of this <span style="font-weight: bold">without</span> the ignition on.
 
martx-5 said:
jsfbond said:
The easy way is to pull the coil wire from the distributor, grab the metal end of the wire and have someone crank the motor over. The harder you hit the opposite wall in the garage will determine how good the coil is... :laugh: <span style="font-weight: bold">Seriously, don't do that unless you like 20,000 volts coursing through your body. </span>
Click to expand...

Good thing you put the disclaimer on there... LOL.
Click to expand...
 
martx-5 said:
The primary winding is measured between the two small posts of the coil. Do all of this <span style="font-weight: bold">without</span> the ignition on.
Click to expand...
Better yet, disconnect one of the low tension wires during the test. Otherwise you may get a false reading if the points are closed/shorted (the ignition warning light is another path to ground).

The resistance test also isn't really a guarantee that it's good. The original Lucas coil for my 56TR3 still checked fine, but the car ran really bad until I replaced it. But since coils rarely fail, I would suspect everything else first.
 
Art, that is just friggin' beautiful. I am still laughing my fat butt off over that one.

:lol: :lol: :thankyousign:
 
Been there, done that... 93 Ford Escort. I back probed the plug boot with a test-light. It'll flash with every spark. neat trick I learned from an old timer. But when I tried to pull the test light probe back out, it pulled the boot off the plug with it. I was still fine till I let go of the negative lead of the test light that I had been holding on the battery terminal. Sounded like this:
"OW! OW! OW! OW! OW! OW!"
The nick name "sparky" stayed with me for years.
 
What all's been done/needs to be done?

- Doug [/quote]
I'm all set up to try starting it. The motor cranks just fine, but I have no idea how to power the ignition system. I need a bare bones make it myself wire set up to the coil etc.
 
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