How to? Electrical tests

[19Charger74]

I'm having problems figuring out a short in my ignition system.

Wondering if someone could help me out or get me going in the right direction.
How can I check to see if the Distributer pick-up coil is good? I know when cranking it should send a signal, but how much? Will a ohm test show its fine?

Also I have a 4 pin ECU. The wires going to the dist don't show any voltage even when cranking. Can i just do a resistance ohm test to make sure its good?

My issue is that i get no spark from coil in start, even through the coil has power. I've also swapped out ECU, Voltage reg, Ballast, Coil, Dist pick-up cleaned all connections, checked all grounds, Checked fuses.

 

[Pops1967GTX]

Here's a good article to start with....
http://www.mymopar.com/downloads/elecignconv.pdf
http://prestoliteperformance.com/Portals/0/downloads/marine/pdf/TS_Points.PDF

http://www.4secondsflat.com/Technical_Information_for_Ignition_and_Carburetion.htm

 

[Meep-Meep]

If you want to check for voltage from the pickup get a small DVM and put it in AC volt range on the lowest scale. Then turn the shaft by hand and watch the needle jump as the reluctor passes the magnet. It's generates a pretty small voltage but that's all it needs to do to turn on a transistor.

 

[19Charger74]

Thanks guys!

 

[19Charger74]

Went out and checked everything again today and everything checks out good... Been reading forums/threads and everything about ignition systems and I still can't get this thing to fire up.

Is there anything that i'm missing?

 

[19Charger74]

I checked my bulkhead connectors today and the power feed from battery and alt looks alittle burnt. I still get power through into the dash, but could this cause it to not fire up?

 

[super-bee_ski]

Another way to check a coil is perform an Ohm check. It should read open or "short".

 

[383man]

You can do an ohm test on the pick-up coil which should be between 150 to 900. But the best test is the voltage test. Just hook a digital voltmeter to the 2 pick-up coil wires and have it on the lowest scale. If its a Fluke voltmeter they are self setting to the proper scale. The pick-up will only put about 1.6 volts ac voltage when you spin it with the voltmeter hooked to it on the ac scale. If this is a Mopar system there is another back yard test you can do and its simple. Just unhook the pick-coil at the dist and then turn the key on and have someone hold the coil wire about 1/4" from ground. All you have to do is take the wire harness end at the dist you nunhooked and scrape the male terminal to ground. Everytime you touch the male dist harness terminal to ground it should spark. If it does the pick-up coil is bad. If not you have other problems. Ron