Test a rectifier on a 1989 Johnson 120

[The Cat's Ass]

Hey, how can I test to see if my rectifier is bad on my 1989 Johnson 120? There's 5 wires coming off it.. Red, Purple, Grey, Yellow/Grey, Yellow. ANy help would be great. Thanks!

Edit: Sorry about that... I think I posted this in the wrong spot. This can be deleted.

 

[racerone]

Are you 100% sure that these motors do not have a rectifier / regulator.----Seems to be shown on the parts diagrams.