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Discussion Starter #1
Please help if you can.

I started the newly rebuilt 289 engine in my '65 today for the first time. I wanted to use the Petronix I bought, but it wouldn't fire. I didn't want to chance messing up the cam, so I stopped and put the points back in. The motor started and I ran it for about 20 minutes to break in the cam.

After shutting it off, I was unable to get it re-started. I pulled the plugs to get a reading and only 5 of them looked like they had ever been used. I pulled the coil wire out of the distributor and checked for spark to ground. I have spark. I checked each plug tower using an extra coil wire and I only have spark on 4 cylinders. I pulled all the plug wires off and they all have the same resistance ~2000 ohms.

I put it all back together, and still nothing. It spit a few times, but won't start.

I put the Petronix back in and checked for spark off the distributor. I get one spark and then nothing no matter how long you crank the engine.

Everything is new: distributor, cap, rotor, plugs, wires, Petronix and coil. And, I've never used any of the parts prior to today.

Anyone have any ideas???

Thanks in advance,
 

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Your rotor might be worn. Whatever the problem is, it is related to the distributor area, as you have good spark from the coil, but not from the dizzy. Stick with the points to solve your problem of bad spark.

Is your cap on good 'n' tight? Is it cracked at all? Just checking...

Your pertronix may not work with low voltage at the coil. It needs a good 6V on the input side of the coil, with 12V preferred.
 

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Discussion Starter #3
Midlife,

Bought another (brand new) cap and rotor (the other ones are new also). No change.

Here's a strange one: I have 12v on the wire coming to the distributor. When I hook up the Pertronix, I only get 6v across the coil. What is causing the drop.

Thanks,
 

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Have you gapped the pertronix correctly? Have you hooked it up properly? The only thing I can think of is that it isn't or it is bad out of the box....
 

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Discussion Starter #5
Mid,

I verified the Pertronix gap with the plastic piece in the kit and with feelers (0.030"). No change.

Only two wires, so I'm guessing I have it wired correctly.

I guess I'll call their tech line on Monday and tell them what resistance and voltage I'm seeing.

Thanks,
 

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Discussion Starter #6
Midlife,

I talked to the Tech at Pertronix. The problem turned out to be (and I've never heard this one discussed) the height of the magnet exciter ring relative to the ignitor module. My magnet ring sat about 0.125" below the top of the ignitor. I put a rubber garden hose washer under it and put the ring back on. The rotor sitll bottoms out fine.

I now have blue lightning spark!!!

The motor fired right up. Go figure.
 
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