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Need Help Locating 1958-1961 w/o generator 40 hp Johnson Mercury Switch

R

RedLeg

New member
Good afternoon everyone,

I need help locating a mercury switch for a 1958-1961 40HP w/o generator Johnson outboard model # RDSL-22-G Serial # 2135771. I have looked all over online for this and seem to keep coming up short. Any help would be greatly appreciated.

So what I think happened was: the controller lever which moves off of the throttle cable to adjust the timing broke while in operation. It looks like when that broke, the linkage ended up breaking the wires and one of two points/connectors off of the Mercury switch. I am currently getting compression, spark, fuel to the plugs like everything it needs for it to start. Its turning over but just not starting despite sounding like its trying. Upon further disocvery I found the broken point and wires on the mercury switch. So this is my last ditch effort to assume thats whats causing the motor not to start. Attached below is a wiring diagram for referance. I am trying to post a picture of the actual switch on the motor but I think its too large. Ill try an embedded link later.

A little back story on the boat, over the winter I complete rebuilt the motor and got it running for the first time in 11 years. I replaced the points and coils, rebuilt the carb, cleaned out the fuel pump and all that stuff. I had the motor running great and had the boat out on the water multiple times late spring. It was all dandy until this control lever broke.

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1. If the electric starter is running even with the wires broken off the mercury switch, it is not wired correctly or you have a car solenoid.

2. The mercury switch, good or bad, won't prevent the motor from starting, assuming the starter runs.

3. If you have a car solenoid, that might be what burned the wire off one section of the mercury switch. Moral: Don't use a car solenoid.
 
Mercury switch is part number 377363@ $29.00. Plenty of them available here at marineengine.com

Warning, if you install a new one, don't connect a car solenoid to it, or $29.00 = poof!!!
 
Everything from the original ignition switch back to the starter solenoid is all original. No car solenoids (to my knowledge) I had the boat running all year but noticed lots of misfiring so I took the motor apart and saw the coils were actual like cracked and broken. Must have made contact with the flywheel spinning around it due to poor adjustment? So I replaced the condenser, points and coils and had it running super smooth up until that one arm/lever broke when I had it out.

Do you by any chance know if it would be possible to find that wiring harness that attaches to the inside of the shroud? The harness goes from the starter solenoid and screws into the exterior of the shroud, then there’s the inside portion. I am looking for a part # for that to see if I can pick up a new one of those as well. If not I found a used one on ebay.
 
I must have been looking at the wrong model pictures or I must have overlooked seeing the harness and the switch in those diagrams. Thanks for your patience I appreciate it. I was able to find the harness used online since its not available here and ordered the switch from here. Hopefully ill have an update in the next week or two on if I get it running.

Thanks again!
 
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