Selector switch for 1971 50hp evinrude model 50172S

50hp

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Need some help wiring a selector switch for 1971 50 hp evinrude model 50172S . I can't figure out which wires goes where I have a green,blue,purple-green,purple. I have 3 prongs on the bottom one has R one has F and one has +. At different times I've had forward and neutral and no reverse than I had neutral and reverse and no forward please help. Motor runs good.
 

racerone

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Are you sure you have the correct switch ?------That system is in forward when motor is NOT running.-------12 volts is applied to green to get neutral.------12 volts is applied to both wires ( green and blue ) to get reverse.---------No voltage required anywhere to get forward gear.-----Motor must be TURNING to provide oil pressure to shift function !
 

50hp

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I'm pretty sure I do it's look like the rest of the one on line I'm thing I have the wiring going to the wrong prong ?
 

racerone

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Is this a new switch you have ?------A new to you motor ?-----Did the problem show up suddenly ?-----Some simple testing can be done.----Interested in how to do this with simple steps , yes or no ?
 

50hp

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I bought the boat,motor and trailer there was no switch, they had it wired to toggle switchs I bought the switch on ebay I wanted it back original because the switch was still available and yes I can take all the wires involved off and started from scratch
 

racerone

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Do you have a part # for the switch you have now.-----There are 2 different switches and step # 1 is to determine if you in fact have the correct one.-----One system needs 12 volts applied to get forward gear.----The system on your motor defaults to forward with no voltage needed !
 

racerone

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That is the correct part #.---Turn ignition switch to on..---With forward button pushed in there should be no voltage to the blue or green wire.-----With neutral pushed in there should be 12 volts to the green wire.-----With reverse pushed in there should be 12 volts to blue AND green.-----Have you confirmed that the wires going into the lower unit are hooked up correctly ?----Green to green.----Blue to blue.----What oil is in the lower unit ?------The solenoids do not move the clutch dog.----The solenoids direct oil pressure.----Motor must be turning to do the shifting.
 

racerone

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Any pictures of the terminals on this 279090 switch.----Just puzzled as to why there is an F as there is no voltage required for forward.
 

50hp

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I'm not sure what wire goes where now the wiring diagram I pulled up has the colors that go to the switch but not what color goes to what prong they go to..
 

racerone

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Purple goes to positive.--------Then try blue to R and green to F------If It does not work correctly then change the blue and the green around.------No damage can be done if they are wrong the first time.
 

50hp

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Does a purple with green stripe go anywhere because the diagram I'm looking at say it goes to the switch
 

racerone

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Purple and purple/ green are the power supply and both go to the same terminal------. One from the battery and one from the blocking diode--------You do have the blocking diode in the controls / wiring I hope.
 
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50hp

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I'm sorry I'm a rookie if there is one present I don't see it I will get one tomorrow and go from there,
 

racerone

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Post some pictures of controls and of wiring on the motor.----Blocking diodes are actually on the motor coming off the terminal strip.----Electric shift / 12 volts / wiring is easy for me.
 
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