Help with wiring start switch to 79 evinrude motor.

tknjk

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Ok here's the deal. I have an older I believe 79' Evinrude 35 horse 2 strode boat motor, and I need to wire a new switch to it.
There are 4 wires labeled 1, 2, 3, 4. in the followinf pics. They are corroded as hell, and fell off the switch. There is a push button
start on the motor, and all the key switch did was apparently turn the power on so the push button could start the motor. I would like to
hook up a simple rocker switch instead of trying to wire up another key switch. I don't know what kind of rocker I would need, but since
the boat runs off of a simple small battery I assume a fairly cheap one would do the trick. Could someone help me, and explain the
way I would need to wire these wires to a new switch??? I would really appreciate it. If not point me to a forum where someone could help me.

28tzv61.jpg

Here are 2 of the wires they both go to the right side of the motor.
I realized that after I posted this pic wire #2 isn't involved. only 1,3,4.
1zgqjqx.jpg

the other two here go to the left side.
65ao2r.jpg

This is the switch that they were originally hooked up to
2e14nkw.jpg

same switch
2vw7j86.jpg

This is just where the wires enter the motor.
 

tashasdaddy

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Re: Help with wiring start switch to 79 evinrude motor.

your existing switch and button, are from the 60's. dash mount, there was a change, where all the functions are in the key switch. 79 used the new system, some one rigged the present set up. wiring color codes do not match, as they have red wires for positive and negative wires.
 

ezeke

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Re: Help with wiring start switch to 79 evinrude motor.

The motor has two wires to energize the starter solenoid, marked S and S on the switch, and two wires to kill the engine marked M and M on the switch.

The wires to kill the engine are a black ground wire and the black and yellow kill wire. You have those marked as 4 and 3 respectively in your last photo.

The wire that you have marked as 2 should have a fuse in line on the way to the switch and be on the other side of the solenoid; that is the positive power for the starter solenoid. When you turn the key to start, the switch closes the circuit with wire #1 in your photo and causes the starter to crank.

You don't need any other switch unless you want to install an emergency kill lanyard, in which case you would cross the two M posts on the switch.
 

tknjk

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Re: Help with wiring start switch to 79 evinrude motor.

The motor has two wires to energize the starter solenoid, marked S and S on the switch, and two wires to kill the engine marked M and M on the switch.

The wires to kill the engine are a black ground wire and the black and yellow kill wire. You have those marked as 4 and 3 respectively in your last photo.

The wire that you have marked as 2 should have a fuse in line on the way to the switch and be on the other side of the solenoid; that is the positive power for the starter solenoid. When you turn the key to start, the switch closes the circuit with wire #1 in your photo and causes the starter to crank.

You don't need any other switch unless you want to install an emergency kill lanyard, in which case you would cross the two M posts on the switch.

The wire marked #2 goes from where you see it and goes directly into a push button start mounted on the motor.
Also if you notice the key switch is kinda messed up. The thing is corroded, and I don't trust it to stay together. Basically what I am looking to find out is can I take those 3 wires, and hook them up to a switch like some sort of a toggle instead of using that key switch? If so what kind of switch, and how would I wire it?
 

Silvertip

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Re: Help with wiring start switch to 79 evinrude motor.

Fix this thing correctly. Buy a new ignition switch (it's not a bank breaker) and wire it like this.

KeyswitchWiring.jpg
 

ezeke

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Re: Help with wiring start switch to 79 evinrude motor.

With reservations, I agree with silvertip:

Firstly, there should be a fuse between B on his diagram and the battery post on the starter solenoid;

and,

Secondly, there should be nothing wired to the other large post (starter side) on your starter solenoid except the starter.
 

tashasdaddy

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Re: Help with wiring start switch to 79 evinrude motor.

totally agree. that is what is was saying you have a rigged system.
 

tknjk

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Re: Help with wiring start switch to 79 evinrude motor.

Fix this thing correctly. Buy a new ignition switch (it's not a bank breaker) and wire it like this.

KeyswitchWiring.jpg

So according to this pic my main pos. cable to the battery is on the wrong side of the solenoid?

Another question. If I take it to a pro to fix what do you think it will run me?
 

ezeke

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Re: Help with wiring start switch to 79 evinrude motor.

tknjk, "(starter side)" of the large post on the starter solenoid in your first photograph should have only the starter connected to it.
 

tashasdaddy

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Re: Help with wiring start switch to 79 evinrude motor.

$80 to $125 per hour.
 

Tim Frank

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Re: Help with wiring start switch to 79 evinrude motor.

I am not sure that there is a right or wrong side of the solenoid. I believe that the large posts are equivalent.
The key point is that the large post to which the starter connects should have ONLY the starter wire. In your pic you have a small gauge wire connected to both large solenoid posts....that is not correct.
Off the top of my head I cannot think of a load (other than the starter) that would require only that momentary connection when the solenoid is energised.
That wire also probably would not be fused and could pose a fire hazard.
 

tknjk

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Re: Help with wiring start switch to 79 evinrude motor.

Well I have a buddy that is into small engine repair. Riding mowers etc. that says he may be able to understand it better than me come over tomorrow, and take a look at it. The boat is old, and ugly, but the motor runs fine, and It's not worth spending a couple hundred dollars to have a pro fix it for me.
 

Silvertip

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Re: Help with wiring start switch to 79 evinrude motor.

Lets get some things straight here. First, the diagram is intended to illustrate the very basic starting circuit only. The solenoid in the picture is actually a Ford solenoid and if yours has one of the small terminals marked "I" ignition, that goes to the "S" terminal on the key switch. If the other small terminal is marked "R", it is not used and I won't explain why. If the solenoid mounting bracket serves as the ground, then what i show as the ground connection should be shown going to the metal bracket but in that case is not a physical piece of wire. The two large terminals on the solenoid have no polarity. You can connect the starter to either one. But remember, the small wire and the large positive battery cable must be on the same terminal. Just follow the picture. It ain't rocket science. A line is a piece of wire. Small engine or large engine, starting circuits are basically the same.
 
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