Wiring diagram needed for my 1972 johnson 50hp hydro-electric drive outboard motor

You have got to be kidding. There is hardly any wiring on a 1957 Johnson. If it is not electric start look at a 1972 6 hp, same wiring.

If I remember correctly, it does not matter as they are just one way switches. That is why the new one is not color coded.

see this video
http://www.youtube.com/watch?v=Md-6H0rfEeI
see the orange thick wire your outboard may be similar notice the spark plug at the back of the motor near the bottom of the engine at the end of the thick orange cable. I recommend looking for a similar thick electrical cable and follow it to where it ends up.

If it's an electric start you need to get it from an after market supplier, Johnson Motors is gone. Go online to CDI Electrical and put in the specific information and it will give you the correct part number for what you need. Here's their part number.Johnson / Evinrude Wiring Harness: 413-9914

Outboard?

Google outboard engine wiring color codes

Symptoms?

It appears you have a Johnson, 40 horsepower, electric start, long shaft (20 inch transom) 1973.

save yourself some money and go get a lawn mower solenoid and find a way to mount it yourself. I have done a johnson outboard and a tigershark jet ski this way with no problems.