1993 Johnson 120 Charger

[michaelhedges]

Does anyone know how to check the battery charger on this motor. The crank battery eventually needs charging and the boats volt meter used to creep to 14volts while the motor is running. This does not happen anymore.

Where is the darn thing also?

 

[tashasdaddy]

Re: 1993 Johnson 120 Charger

replace the rectifier, have you by any chance connected the battery cables backwards for just a second. if so it blew the rectifier. the rectifier converts the ac power from t engine to dc to charge the battery.

 

[Walker]

Re: 1993 Johnson 120 Charger

The best way to check that charging system is with an amp meter. I'm at work and if you don't get the procedure before tomorrow I'll look it up and post around noon when I get home.

 

[Silvertip]

Re: 1993 Johnson 120 Charger

You don't need an amp meter. He already has a voltmeter. If its not reading 13.6 volts or so at mid to wide open throttle the battery is not charging. If the voltmeter is not reading anything, the meter itself is bad or has become disconnected as it should at least measure battery voltage. If you have a hand held voltmeter check voltage at the battery with the engine at 1500 RPM or so. If its charging it should measure something above 12.6 volts. If you haven't cleaned battery cable terminals (both ends) and checked for corrosion you need to do that. Bad connections will not allow the battery to charge. You may also have a battery that's on its way to battery heaven.

 

[michaelhedges]

Re: 1993 Johnson 120 Charger

Checked amp. thru the volt meter and I get nothing. Voltage on battery stays the same while the engine is running.

Does any one know where it is?

 

[Walker]

Re: 1993 Johnson 120 Charger

Sorry I didn't get back sooner. Here's the procedure for testing alternator output. Disconnect the rectifier/regulator lead from the starter solenoid. hook up an amp meter between the lead and the post you took it off of. Start the motor and you should see the amps climb as you accelerate the motor. Don't rev it over 1500rpm, That will be fast enough to see if you are getting any charge.
If you get nothing then you need to determine whether the problem is the stator or the rectifier.