How to wire 1971 Evinrude Ski Twin 40 hp

[Terry Porath]

I just purchased a 1971 Evinrude Ski Twin Model 40152B and need help in deicphering the wiring. The boat previously had a Johnson 40 hp and the wiring had the quick release on the side of the motor. The Ski twin is hard wired inside the motor so I am going to have to disconnect the wiring from the previous motor in the panel box and wire the new one in. The wires on the Ski Twin consists of: 2 black, one white, one red and one purple. Its hard to tell in the panel box what goes where so I need a starting point. Does anyone have the wiring diagram that would help out? Thanks-Terry

 

[F_R]

Re: How to wire 1971 Evinrude Ski Twin 40 hp

Take that junction box out and sell it, it is worth some $, and you don't need it for your '71.

I don't have the diagram, but is the red actually red with purple stripe? That would be the "hot" wire going to the "B" terminal on the ignition switch. The purple wire actually purple with white stripe? That goes to the choke switch. The two black ones are the kill wires, go to the "M" terminals on the ignition switch. White is the start wire, goes to the "S" terminal on the ignition switch.

 

[Terry Porath]

Re: How to wire 1971 Evinrude Ski Twin 40 hp

Thank you for the response! That was the conclusion I was coming to - to completely remove the panel box.

Yes - the purple wire does have a white stripe, but the red is solid red. The previous motor did not have a choke switch. Do I need to locate and install a switch and if so is there a specific one I need?

Also, at some point the previous owner installed a spacer on the lower end of the motor to convert it from short shaft to a long shaft. A short shaft is going to be better for the boat I am using it on. How hard is it to remove the spacer to convert it back to short shaft?
Thank you for your help! Terry

 

[F_R]

Re: How to wire 1971 Evinrude Ski Twin 40 hp

The choke switch can be any momentary push button switch as long as it will carry a few amps. Just don't get TOO chintzy and you should be ok. Use a short wire between the "B" terminal on the key switch and one side of the choke switch. Purple/white goes to the other side of the choke switch.

Changing back to short shaft is the same job, labor-wise, as changing a water pump. But you will need a short drive shaft and the shorter bolt at the rear of the gearcase. Hopefully, the other stuff will have extensions on them that you simply remove.