key switch trouble

[stratcat88]

hey guys, got rid of all my boats so its been awhile since i have been on this great forum. sad to hear that Don S passed. what knowledge. about a month ago a customer of mine gave me a 1850cc pro sport center console with a 115hp yamaha outboard. no #s on the motor anywhere. their are a few things that need fixing, because of sitting on the trailer for a year. so the first thing im going to tackle ic the key switch. its seized up. tried wd and mouse milk, but no go. i went to west marine and the guy sold me a sierra mp39090 ign.switch. it has 6 term. on it like the bad switch, the old sw. has 1- M terminal where the new switch has 2-m terminals. a marine mech. i know told me to mount the new sw. with the 1-m at 2oclock and just go wire for wire counter clockwise. i don't know man it doesn't sound right to me. yammy dealer wants 170.00 for that sw. i payed 36.00 for the sierra sw. any comments would sure help me out. thanks a lot

 

[mjf55]

Lets see if this helps at all. This link shows what the function of each terminal does ​http://forums.iboats.com/forum/engi...witch-1995-force-120-hp?p=6529829#post6529829. the jest of it is:
M1 -WHT OR BLK/YEL - this is nothing but a ground wire for shutting the engine down. It should have continuity to ground
M2 - BLU OR BLU/BLK (Usually there are bundle of wires here use to ground or kill the engine by shunting the CDM's to ground via M1
I - RED/BLU - aux power wire
C - GRN OR YEL/BLK - choke wire
S - YEL OR YEL/RED - this runs straight to the starter solenoid via the neutral switch
B - RED - this one is really easy to ID by doing a voltage test. This a hot wire should read 12V to ground - battery wire

Since you do not have the year / model, I ASSUME you do not have a service manual for your engine. For My 1989 175, my key switch ( not a push to choke ) uses colors Black, White, Red, Yellow, Brown and the choke switch uses Blue and yellow. the switch connects the following :
OFF- B and W
On - R and Y
Start - R and Y and Brown

Now, according to this link http://www.maxrules.com/fixyamahawiring.html, the Yamaha color codes and definitions are:
Black - Ground
Red - +12 volts unswitched
Yellow - + 12 volts after the switch
White - Engine Kill circuit ( goes to CDI )
Brown - Start Circuit
Blue - Choke.

Hopefully you have the same colors at your switch. So combining the 2 tables would be

M1 - White ( Kill)
M2 - Black (Ground)
I - Yellow (Ignition)
C - Blue ( choke )
S - Brown ( to starter solenoid )
B - Red ( Battery + 12 Volts )

However, that is my interpretation of the data I found, not sure it is correct Hope it help

 

[stratcat88]

hey mjf55, thanks a lot for the info.on the old sw. are the blacks. does it matter which black goes on m1 and which one on m2? my wire colors are the ones you wrote last. so if i put yellow and red together and just touch brown should engage the starter?thank you again for the help.

 

[mjf55]

stratcat, I am confused by the first question, if you have the wiring colors I posted, then you only have one black. How many blacks do you have? How many wires are at the switch?
Second question, yes that should start the engine.