Yamaha 9.9AE not Charging?

[stratos1]

Recently purchased a Yamaha 9.9AE for our little cruiser and at first it was fine however, it now runs erratically and also now does not charge up the battery. I used to get a healthy 13.8 - 14 volts but now nothing.
Not sure if the erratic running and charging are related??

Any help appreciated - outboard newbie!!

Cheers

[boats.net]

The alternator circuit and ignition circuit are different and shouldn't have any affect on each other, need to test rectifier and check for for spark on all cylinders.

[stratos1]

Sorry, when I meant erratic I should have explained more.
It is not a spark issue (my diagnosis), i believe it's more fuel or electronics.
One minute it will be running fine then the next it's slowing down, speeding up all on its own, when it slows, it often stalls.

Can you please tell me how best to check the rectifier??

[boats.net]

May have a fuel restriction, engine may be starving for gas.
The service manual has the test chart for testing rectifier, www.yamaha-motor.com has manuals.