Tach not working

[V-King75]

I have a 84 V-King with an Evinrude V4 140 stamped 83 production. I have replaced the tach and also the voltage reg without success. I do not have the repair manual and was hoping to solve this with some help on here.

John

[Hippie459MN]

I cant help ya much as I am not that savvy with the electronics on the motors but I do have a service manual that someone sent to me that I uploaded to my server if you like. It has helped me alot big time in getting a few things on my 175 taken care.

Just right click the link then select save target as or save link as.
http://www.hippie459mn.com/downloads/1973-1989_Johnson_Evinrude_Outboard_Service_Manual_48-235_Hp.pdf

Hope that helps some.

[ccrick]

I bet 77viper could help

[77viper]

Check continuity on your gray wire from the volt regulator to the back of your gauge.
Check for power on your purple wire and a ground on your black.
Did you change anything or did your tack just quit working?

[V-King75]

77Viper,

I have learned on my motor the lead for the tach comes off the rectifier. The voltage reg has a yellow wire that goes to terminal one of the strip and the purple wire goes to the terminal six. The yellow wire from the rectifier goes to the terminal which connects to the grey wire that goes to the control box.

[77viper]

Ok I was wrong and thought the signal came from the reg. but it makes more sence if it came off the rectifier. I have a hard time not seeing these things as I don't work on that many motors from the 80's. I would still check for continuity on the gray to the rectifier.

[V-King75]

I believe I have a bad rectifier... Checked it with an ohm meter.. Will have a new rectifier by the weekend

[77viper]

After a new tach that would be my guess. I hope it works.

[V-King75]

well, still no tach.... must be some bad wiring... Anyone know what the voltage is at the input for the tach?? I know i have voltage drop from the control box vs the tach input

[77viper]

What is your voltage on your purple wire? should be 12 volts
Do you have a good ground on your black?
The gray is ac voltage, I'm not sure off hand what it is.
Do you have continuity on gray all the way back to the motor?