50hp 72 Evinrude electric shift control wiring question

kippstakes

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opened up my shift selector box and noticed that the green wire was connected under the reverse switch, and the blue under the neutral switch. from my understanding, the blue goes the the reverse solenoid and the green to the neutral. the strange thing is that i've been running with this wiring config for a while with no problems.
could it be correct? or should i switch them to the manual's configuration?

thank you
 

Joe Reeves

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Re: 50hp 72 Evinrude electric shift control wiring question

If it ain't broke... don't fix it!
 

kippstakes

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Re: 50hp 72 Evinrude electric shift control wiring question

true, but i'm concerned that it might work both ways but better if correct- and possibly do damage otherwise. MOST schematics say blue is reverse, but i've found just a few that say green is correct. strange and concerning.
note: the other day when i had the boat out, and at speed, the lower unit popped into reverse spontaneously (and to my great surprise), and luckily didn't shred my trans gears.
Can't imagine how this happened- absolutely certain the button didn't get bumped. this is why i opened the shift selector, to install a reverse switch so i can disable it while i'm under way.

suggestions?
 

F_R

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Re: 50hp 72 Evinrude electric shift control wiring question

opened up my shift selector box and noticed that the green wire was connected under the reverse switch, and the blue under the neutral switch. from my understanding, the blue goes the the reverse solenoid and the green to the neutral. the strange thing is that i've been running with this wiring config for a while with no problems.
could it be correct? or should i switch them to the manual's configuration?

thank you

You are doing too much assuming. You are assuming that "under" means "connected to". Not so. Your switch is connected correctly. And yes, green is neutral and both green and blue together make reverse. I have no idea why your motor suddenly jumped into reverse while at speed in Forward. While in Forward, there is NO voltage to either one of the blue/green wires. Also, if it is set up correctly, you should not be able to press the buttons at speed. The white sliding interlock in there is supposed to prevent that. Sorry, but I don't have the 50hp diagram, but the control is the same as this 65hp.
 

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kippstakes

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Re: 50hp 72 Evinrude electric shift control wiring question

Okay, I did some experimenting today to be sure.
It looks like the blue wire does go to the reverse solenoid.. however it connects below the neutral switch. in other words, when the blue wire (below the neutral switch) is disconnected, I can no longer shift into reverse, and when the green wire (below the reverse button) is disconnected, i don't get neutral. I don't quite understand the inner layout of the actual switch's wiring, but it seems odd that they would be reversed like that.
does this sound correct?
I just don't want to get out on the water and have my wiring/solenoids go to pot suddenly because of lurking wiring issues.
 

Joe Reeves

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Re: 50hp 72 Evinrude electric shift control wiring question

I have a problem understanding what you're speaking about... sounds like you're over complicating a simple circuit. The mentions of "under" and "below" tells us nothing. The neutral safety switch simply eliminates the voltage to the starter solenoid windings so that the starter cannot be engaged when the engine is in gear. The following may be of some use to you.

(Hydro Electric Shift System Explained)
(J. Reeves)

NOTE 1 -The ohm reading of the individual shift solenoids should be between 5 to 6 ohms. The ohm meter should be set to low ohms. The shift wires leading to the solenoids must be disconnected when being tested.

NOTE 2 - The solenoid plunger measurement must be made with the solenoid placed within the lower unit. The measurement must be approximately 1/64" beneath the top surface of the solenoid... NOT above the solenoid surface nor any lower than 1/64" of the solenoid surface. This factory measurement is critical and will not ever change UNLESS someone has tinkered with it.

The shifting setup of the lower unit is what's called a "Hydro Electric Shift", which is quite complex consisting of voltage being applied to solenoids in the lower unit which in turn change oil passages via a oil pump that supplies various pressure on a spring loaded shifter dog. The wires leading to the lower unit (at the powerhead) are "Green" and "Blue". The engine must be running or cranking over in order to shift out of forward gear.

You CAN NOT use HI VIS lube in that lower unit. You MUST USE what OMC calls "Premium Blend" lube, commonly called "Type C". (A thinner lube)

Note: The engine must be running OR have the driveshaft turning by some other means in order for the engine to shift.

In neutral, you need 12v to the "Green" wire.
In reverse, you need 12v to both wires, the "Green" one and the "Blue" one.
In forward, there should be no voltage to either wire. (The spring loaded shifter dog forces the unit into forward gear)

To check the lower unit for proper shifting to make sure you have no trouble there, remove the spark plugs to avoid problems and to allow a higher cranking speed.

This next step eliminates the actual shift switch in case problems may exist there.... Disconnect the blue & green wires at the knife connectors (the rubber insulated boots) leading to the lower unit at the powerhead, then using jumpers, take voltage direct from the starter solenoid to apply voltage to the "Green" wire for neutral, then both wires 'Green" & "Blue" for reverse (Remember the engine must be cranking over in order to shift).
With no voltage applied, the unit should be in forward. No need for a ground jumper... the lower unit's already grounded. You may crank the engine with the key switch or by energizing the starter solenoid with a jumper wire.
 

kippstakes

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Re: 50hp 72 Evinrude electric shift control wiring question

Thank you, I think I figured it all out. Correct, making a simple issue complicated.
Working fine and ready to sail!
Thanks again
 
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