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72 Johnson 115 Electrical Issues

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Matthew72Johnson115

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I recently acquired a Glastron boat with a 70's model Johnson 115. The first issue I noticed was the tach was not working and the battery was not being charged. After wiring inspection I found that the rectifier was corroded and bad. I purchased a new one and installed. Boat started fine and I proceeded to adjust low speed idle over the next few days. On the latest startup I noticed that it kicked itself into gear so I turned it off quickly pulled the engine cover and smelled something electrical. After inspection I noticed my clipper circuit had failed (smoked) and an overvoltage was sent to my drive solenoid resulting in failure. Can someone shed some light on this issue??
 
The "Clipper Circuit" proved to create more problems than it cured and OMC issued a bulletin that it be removed from the circuit.
 
The battery charging amperage of the stator on that model engine is quite low.... I'm at a loss to understand how it could possibly overcharge (increased voltage).

For the clipper to actually overheat to a point where it would be smoking is something I've never encountered either. I can only assume that in the past 44 years, someone has rewired a few areas incorrectly. Hopefully you have a wiring diagram and can check that out.
 
joereeves I found a diagram online and started tracing the wiring out. I assumed when I wired the new rectifier in to replicate the way the old one was wired since the boat has run in the past. This proved to be incorrect, someone had pulled the 12v power wire off the feed to the rectifier and taped it off, so when I replaced the part it did not have its supply power from the starter solenoid. What I'm still trying to wrap my head around is why this would have caused the overvoltage to the drive solenoids? Was I possibly getting AC power from the stator? Was the clipper circuit trying to correct this voltage issue and finally gave up the ghost? How can I protect the new shift solenoids and wiring that I just dropped 400$ on down the road?
 
NO, NO----------The rectifier supplies power to the battery for charging purposes and that goes to the battery at the solenoid.------ Red wire from battery and red wire from rectifier are on the same post.---------------The rectifier does not use power it supplies power to recharge the battery !!
 
racerone, thanks for the word-smithing let me restate.... both the yellow supply wires going to the rectifier looked to be wired correctly receiving power from the stator. But the red supply wire to the starter solenoid was lifted by the previous owner for some reason. Still trying to figure out how my drive solenoids got fried....
 
Both shift solenoids should have the same ohm reading.---------Green to the engine block reads what on your motor.-------Blue to the engine block reads what on your motor ?
 
Before I pulled the lower unit off the blue wire read around 6 ohms and the green less than one. When I read voltage from the remote control during this time it was 12vdc with key in on position and around 180vdc when running. After removing the smoked clipper circuit and leaving the rectifier wired like orginal owner had I still had the high voltage during engine run. Last night I wired the rectifier like the schematic I found online I have 12vdc with key forward and 12vdc when running.
 
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