1971 Johnson 60hp cdi box issue

Joined
Jul 19, 2021
Messages
16
Did you follow my instructions in your other thread exactly? If you did, you probably have a bad amplifier or coil. Take your pick. BTW, it would be better to stick with one thread so we can follow your progress.
So I did your test again because I had a feeling i did it incorrectly but still no spark. So I tried the old amplifier to give it a shot and ofc spark was at the spark gap. So I screwed the coil wire back into the distributor cap and could hear what sounded like spark whenever I touched the points wire to a ground but no spark out of the spark plugs. I reassembled everything to give it a shot and there was spark in the spark plugs but it wasn’t consistent. I really only sparked as soon as I turned the ignition off.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,499
Make sure you have a big battery.----Load test the battery.-----Take starter apart for inspection.----Test the starter armature for short to ground.
 
Joined
Jul 19, 2021
Messages
16
Make sure you have a big battery.----Load test the battery.-----Take starter apart for inspection.----Test the starter armature for short to ground.
Sorry I’m asking so many questions I’m just trying to learn. Why do I need to inspect the starter if it turns over fine. Also I don’t really know what a starter armature is and how it would affect spark.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,499
There is a wonderful opportunity to learn here on your part.----But you are questioning my simple tricks.------Some trouble shooting on your part needs to be done.----Maybe return the possibly defective parts.-----Ignition trouble shooting guide may be found on line.----I started repairing these motors when they were new !!
 
Joined
Jul 19, 2021
Messages
16
There is a wonderful opportunity to learn here on your part.----But you are questioning my simple tricks.------Some trouble shooting on your part needs to be done.----Maybe return the possibly defective parts.-----Ignition trouble shooting guide may be found on line.----I started repairing these motors when they were new !!
The batteries are fine they’re two brand new high output diesel battery’s. I inspected the starter and it all looks normal and still works.
 
Joined
Jul 19, 2021
Messages
16
That probably is ok. You need to isolate the problem before fixing things or buying expensive parts.

1. Disconnect the coil and unbolt it from the mount. Now remove it from the distrubutor cap by unscrewing the wire frpm the cap (rotate the whole coil & wire to unscrew it.)

2. Remount the coil and rig up a spark gap off the end of the threaded terminal. Reconnect the primary wire.

3. Disconnect the wire leading to the points.

4. Turn ignition switch on.

5. Lightly brush the points' wire across an unpainted, grounded surface. You should see a flurry of sparks across your spark gap. If you do, everything up to that point is working and your problem is elsewhere, such as points, distributor , etc.. If no sparks, work backward through the circuit, starting with the voltage at the purple wire input to the amplifier. Should be close to 12 Volt.
Alright so I connected a spark tester and I’m getting light spark when I turn the key. Once I turn the key off I get a full spark in the tester light and in the spark plug. Any advice?
 

Hab

Petty Officer 2nd Class
Joined
Jul 4, 2017
Messages
158
Sounds like your cdi is wired incorrectly. The cdi box should only discharge to the coil when the points open. On my cdi box there are 4 wires. 12v supply voltage, 12v to the points, a tach signal, and a coil discharge. If your wired differently. Stop and find the wiring diagram for the cdi box. If your wiring is right, you can move on to other tests. Your getting some spark, so you cant be far off. Just be darn careful with those expensive cdi boxs. Post some pics and well see what we can see.
 
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