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Missing safety switch 1967 40hp Seahorse

T

toadshade

Member
When I got this old engine the white wire on the vacuum cut-out switch was disconnected. I see in the manual it connects to a safety switch that I suppose is missing. I don't see it on the engine diagrams. There is a bolt where I assume it is supposed to go. A couple questions: What reason would someone have to remove this switch and what could happen when I install one and hook it up correctly? I would like to get the cut-out switch working properly again.
 
Itam #50 switch. Mounts on Item #53 bracket

http://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1967&hp=40&model=RDS-29&manufacturer=Johnson&section=Powerhead+Group
 
It was put there in case the motor ran away with itself. It would kill the spark on one cylinder.
 
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There is a " cutout switch " that cuts off ignition to one sparkplug when very high vacuum is present.----There is a " safety switch " under the magneto plate that prevents the starter from working with too much throttle applied.-----Sometimes when these things do not work or folks do not understand how simple they are , they are thrown out / discarded.
 
The safety switch performs two functions.

1. It limits the vacuum cutout switch to operate at slow throttle settings only. This prevents a possible high speed miss under certain conditions.

2. It prevents the electric starter from operating at high throttle settings. A serious safety issue. Think what would happen if you were to accidently start it in gear and wide open throttle. What would you run over? The pier? Another boat? A kid?
 
All valid. I completely agree. I am planning to put it back. Cheap and seems to be an easy install. I have not looked to see if there is an adjustment or tolerance when installing. But I can't believe this stuff is just ripped off the engine. The auto choke wire is disconnected and there is another red wire that is disconnected too that I have not traced yet. The only reason I keep going with this thing is that it starts right up and idles perfectly. It is worth getting going I think. Just don't know a damn thing about it yet.
 
Red wire #1 goes to overheat warning light
Red wire #2 goes to electric shift (if equipped)
Red wire #3 with white stripe, goes to choke
Might have another one for a tachometer or voltage gauge (if equipped)
 
It would be nice if one of those was just a disconnected overheat light. That is something I intend to get working before it goes in the water. It has one of those black plastic clips on the end but I cannot find where it connects. It is on the main harness under the carb. But not the choke or the electric shift.
 
I just checked and it is the red with white stripe. It goes into the harness that ends up under the vacuum switch and disappears. I would have to get into the harness to find where it goes. Doesn't seem like the choke. And the wires coming from the electric shift are black and green at least going down to the disconnects down the shaft.
 
It looks right according to the diagram. Funny, on the 1967-68 electric shift wiring diagram (4-112 bottom) in the Seloc, there is exactly ONE wire labeled with a color and it is the red and white choke wire. But the wire that I am following goes back towards the engine under the vacuum switch.
 
Nothing. It was one of the separate disconnected wires. That solved it. It was not only disconnected though it was cut short so it was not obvious that it must have had a clip on it. I was just curious that it went back to the engine, not to the instrument cluster like the diagram. Makes me wonder if I am looking at the same thing.
 
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