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Johnson Ignition module compatibility

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Capnstern

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Hi. I currently have a 1985 Johnson 100hp commercial outboard. I did observe spark on all 4 cylinders while I was running a compression test but now after hooking it up to a control box, I have one bank dead. I know the oem power packs have a 5700 rpm rev limiter. I have 2 packs and timer base from another motor that I can use if my pack tests bad. Does anyone see any issue using a pack without rev limiter one one bank only providing I match the pinouts properly or should I swap everything out to not have to splice anything ? Of course i don't plan on exceeding the limiter. I also plan on troubleshooting with a DVA before I do anything. I prefer to properly test parts rather than swapping and hoping for the best.
 
On a 1985 motor the first things I would do is ------Charge the battery.----Load test the battery.----Inspect battery cables.-----Take starter apart for inspection / new brushes.
 
The motor starts, runs and charges. I noticed one bank was cold and determined no spark on that side. Starts really easy, but no fire per timing light plus no rpm drop when I pull the plug wires. I know the cranking speed has to be enough rpm's to produce enough voltage to spark correctly.
 
Problem ended up being the power pack. I am going to replace the other pack I have on the motor that has a rev limiter with one that does not. I removed the wire pins from the rubber boot and swapped boots. Fyi, If anyone ever needs to remove wires from a rubber boot electrical connector, its very easy to do. Thanks for the advice!
 
Another tidbit to pass along. I have discovered that voltage on the kill switch wire killed my first power pack. I put the replacement on and got spark back, but was concerned about voltage on the kill wire, so I didn't hook up the shifter box cable. Apparently, the kill wire is picking up stray voltage from inside the big red amphenol plug on the motor. I have removed the factory electric tape to see if there is a short in the harness. While wiggling the wiring where it goes into the harness, I see voltage on the kill wire vary from 5 to 7 volts. Just passing along what I've learned to help someone else down the line.
If
 
yes had same problem, but went thru a second P/Pack, at the time in Bahamas, solution was , in the red plug push pin for kill wire back so not making contact, but now turning the key off won't turn off engine, just push key in and choke engine out, never found short, sold boat years later as is
 
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Both kill wires had voltage. I'm not sure why it didn't fry both of them. I originally had spark on all 4 UNTIL I plugged in the control box. I swapped in another harness from my parts motor as you could see bare wire where the harness wiring went into the engine side of the red plug. After installing the "new" harness, the kill switch voltage went to zero. Just before I hooked up my control, I pulled the kill wires on both power packs to test the whole circuit and I am getting 9-10 volts in the circuit with the control plugged in. I looked at J.Reeves troubleshooting info and he states to remove kill wire from the ign switch. If voltage disappears, then switch is bad. Kill switch wire goes to zero volts when unhooked from Ign switch, so I assume it's bad.
 
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