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1958 Evinrude Lark 35hp Ignition wiring

S

Swendsoa

New member
Hello Everyone,

I'm wondering if anyone can help me with wiring in a new ignition switch. I have a 1958 Evinrude Lark 35hp with a 3 position 4 terminal ignition switch and I went to the boat store today excited that I might be able to finally get this motor started today. I bought a 6 terminal 3 position starter from them because they told me it would work I just wouldn't have to use all of the terminals. When I got home and took it out of the package I realized that I didn't know which terminals needed to be used. the new ignition switch is a sierra MP39760 and has a wiring diagram shown below.
attachment.php

Now the real question. The old ignition switch has the two M terminals and a wire attached to each one leading to the upper cylinder armature plate assembly and the other leading to the cutout swtich and then on to the lower armature plate assembly. The new ignition switch has one of the M terminals going to ground and the other going to the magneto system. Can I connect both of the M terminal wires to the outgoing M terminal on the new ignition and the connect the seccond M terminal to ground? Also, On the new ignition switch will I need to connect anything to the I terminal, ignition circuit?

Thank you
 

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The engine "Kill Circuit" of the 1958 35hp Evinriude is as follows:

Remove/disregard the black wire going from the "M" terminal to ground as that pertains to the later solid state ignition.

No need for anything to be attached to the "I" terminal.

(Ignition Kill Circuit)
(J. Reeves)

Two Black wires lead from the Armature plate point sets to the ignition switch. One of the wires leads to one of the "M" terminals of the ignition switch. The remaining black wire leads to the remaining "M" terminal of the switch.

When the key is in the OFF position = The two "M" terminals are connected,. effectively shorting/killing the ignition.

When the key in ON position = The two "M" terminals are not connected and the ignition is engaged.

*At the armature plate.... each one of those black wires is attached to one set of the dual points. When the wires touch each other (internally at the ignition switch) when the key is turned to OFF, that effectively connects the points together, shorting out the ignition.
 
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Thank you for your reply J. Reeves but I'm not sure that I understand your answer. There is only one M terminal that leads to the Magneto circuit on the new ignition switch and one that leads to ground. I understand the part about the M terminals ON and Off Position of the old ignition switch but there is only one M terminal that leads to the magneto circuit according to the diagram in first post. Since the new ignition switch only has this one outgoing M terminal should one of the wires be attached there and the other to the I terminal? Or is this switch simply not going to work?
 
The "M" terminals do not lead to anything unless you hook up wires to them.

Your mind is locked into the idea that one of the "M" terminal must lead to a ground.... This is not so... It depends on what kind of ignition the engine has..... Your engine has MAGNETO ignition... NOT solid state ignition that requires the ground wire.

Your old switch had two wires leading from the armature plate to the "M" terminals..... attach those two wires to the "M" terminal of the new switch exactly as your old switch was, one wire to a "M" terminal... and... get rid of the notion that a ground wire must be attached to one of the "M" terminals.

The internal working/connection of the two "M" terminals of the switch is:

Key ON = "M" terminals NOT connected = Ignition engaged.

Key OFF = "M" terminals connected = Ignition disabled.
 
With wiring being talked about maybe Im at the right spot but not sure, new to forum. I have a 1958 Lark and the motor did not come with a wiring connector, when I try and trace down the pin to what they go to I get continuity on three of the pins when I test the starter pin and the choke could there be a short in the unit or how do I test what pins go to what. thanks in advance on any help passable.
 
Are you talking about the two fuses in the junction box? Those fuses are for the generator and power takeoff. They have nothing to do with the ignition switch.
 
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