25hp Motor Mariner Not Charging

[grady94]

I have a 1985 Mariner outboard, serial # A148102. It does not charge the battery while running. How does one check the charging circuits?

 

[Barnacle_Bill]

Re: 25hp Motor Mariner Not Charging

Check the voltage with the motor not running then again with it running. You should see an increase in voltage as RPMs approach 2K. Most common failure is the rectifier. If you have ever connected the battery up backwards or caused a spark, its shot.

 

[grady94]

Re: 25hp Motor Mariner Not Charging

Do you check the voltage at the battery with the motor running or at the rectifier?