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Johnson 40hp Won't Crank

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Maxanoava13

New member
Hello. I have a 1968 Johnson 40 outboard. It will crank over all day long with the throttle closed, but stops cranking with the throttle open. One wire on the solenoid has no power when cranking, and has power when throttle is moved. Is there a sensor under the flywheel? I'm lost at what could be causing this.
 
There are two wires attached to the two small 3/8" terminal nuts of the starter solenoid.

One wire is (usually) white and has 12v applied when the key is turned to START. The other wire is (usually) black and leads to a safety switch that is actuated by the magneto armature plate. That safety switch is located under the flywheel, on top of the powerhead, on a flange attached to the exhaust baffle plate of the port side of the powerhead.

It's purpose is to prevent unknowing boaters from starting their engine at a high rpm which could (and has) resulted in injury... and also to prevent a run-away engine condition that can take place when one starts a engine in neutral at a high rpm. A runaway engine becomes a diesel engine whereas turning the key off, pushing a stop button, or even yanking the spark plug wires off does absolutely nothing!...... And by the time you can figure out some way to stop it, connecting rods are flying out the side of it.

Whatever you have planned.... leave that safety switch alone! :)
 
Thanks for the quick reply! Is there adjustments for that switch under the flywheel? It should allow SOME throttle before it kicks out so I can start it, correct?
 
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