What's the purpose of a diode?

[72 Roody]

Have a 72 Rude 65hp, and have replaced everything in the ignition system, and came across a part called a diode on the engine diagram. Is the diode the cluster of wires wrapped in a sheeth of black plastic at the top rear of the motor, or am I looking at the wrong thing. And what is the purpose of this diode thingy! Thanks

 

[ezeke]

Re: What's the purpose of a diode?

Diode basically allows current to flow in only one direction. They are used in alternators to allow alternating current to be converted to direct current so that you can run your DC appliances and charge your batteries.

In the 1972 65Hp you found them in the rectifier as well as in the wiring circuit for the electric shift.

http://www.bcae1.com/charging.htm (scroll down)

 

[72 Roody]

Re: What's the purpose of a diode?

This shouldn't cause a lack of spark to the plugs, should it?