1989 johnson 8hp charging circuit

[robert53a]

Hi I just got a 1989 johnson 8hp outboard. It has a charging circuit. What is the best way to test this to make sure it works. Currently the leads are isolated and taped off taped off. Thanks....Robert

 

[robert53a]

Re: 1989 johnson 8hp charging circuit

Just hook up a battery and try it? Any body else had any experience with a small motor charging circuit?

 

[Moody Blue]

Re: 1989 johnson 8hp charging circuit

Hook up a battery (make sure polarity is correct). Measure battery voltage with motor OFF. Should be about 12Vdc.

Start motor and measure battery voltage again. It should be higher than 12Vdc if the charge circuit is working. The higher the RPM the higher the charge voltage. Don't run the RPM's up too high in neutral.

 

[Haffiman]

Re: 1989 johnson 8hp charging circuit

Does it have a light(AC) circuit or a charge circuit??
If only 3 yellow leads from under the flywheel, you will need a rectifier to get DC and charging.
However the output will at the max be around 3Amps (12Volts) at 5000rpm which will effectively give some 1,5-2 Amps charging into the battery.

 

[robert53a]

Re: 1989 johnson 8hp charging circuit

Hi, I think it is a charging circuit, it has a rectifier ( small round canned component) I will do the voltage test with my multimeter. Do I hook up my meter in series with the positive lead? one lead to positive side battery and the other hooked to the positive lead from the motor? Thanks, I'm not much of an electrician.......Robert

 

[Moody Blue]

Re: 1989 johnson 8hp charging circuit

Meter is connected in parallel. (+) meter lead to (+) battery terminal, (-) meter lead to (-) battery terminal.