merc key switch wiring

skip44820

Petty Officer 2nd Class
Joined
Dec 13, 2020
Messages
174
Well its never easy for the old ones. I rebuilt the carb, put new impeller in and go to start and no key switch. ****!!! Bought the motor 2 weeks ago finally got time to work on it and now this. I looked at the color diagrams on file for a 1979 35 merc 2 stroke and it says purple with white choke, purple ignition, blk ground, red with purple plus battery, blk yellow stop, yel with red starter, thats great. I only have solid yel. solid red, solid black, solid white, solid pink. there is a choke switch still in control box with a wire but i paid no attention to color. This is never easy. Now what I do??? Should I hook black and red up to a switch and start adding wires till I find the choke wire, Now I only have 3 to identify. What do you suggest. I ordered a switch and I should have Fri.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,526
It sounds like you have the old wire colors. maybe your motor is older than 1979.

Choke wire is grey. You should see white wire to one side of choke button for ignition power, and grey on the other side of choke button.

White is ignition power, red is battery, yellow is starter solenoid, black is ground, salmon (or orange) is ignition killer and brown is tach signal.

When key is off, black is connected to salmon wire to ground ignition. When key is on, red is connected to white and salmon is open. When key is in start position, red is connected to white and white is connected to yellow to crank motor. Choke works in ign key on or crank position.
 

skip44820

Petty Officer 2nd Class
Joined
Dec 13, 2020
Messages
174
It sounds like you have the old wire colors. maybe your motor is older than 1979.

Choke wire is grey. You should see white wire to one side of choke button for ignition power, and grey on the other side of choke button.

White is ignition power, red is battery, yellow is starter solenoid, black is ground, salmon (or orange) is ignition killer and brown is tach signal.

When key is off, black is connected to salmon wire to ground ignition. When key is on, red is connected to white and salmon is open. When key is in start position, red is connected to white and white is connected to yellow to crank motor. Choke works in ign key on or crank position.
very good, thank you surely helps. now i got motor running but i have a heat problem. have had lower unit off 6 times, motor dont want to pee. I found pieces of old impeller inside the water pump howsing last time, thought i had things figured out but still no pee.yes i had put new impeller in. I dont think i am a echanic . my mariner just bought used 1995 15 hp. hooked to water and no pee. Replaced pump still no pee. Things are not going well for the old one
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,526
That old 35HP motor should have a telltale very soon after starting it on a flusher, as it likely has no thermostat.

That newer motor may need for the thermostat to open before you have a telltale. You might research to see if that is accurate.
 
Top