outboard not charging battery

[mrjigger]

A guy I work with is having trouble with his 1989 100hp merc.

His starting battery is not staying charged. A couple questions.

First of all, he just had his stater replaced. What is a stater and could this be part of his problem.

Does an outboard have something similar to an alternator on a car. Maybe this needes replacing as well.

thanks.

[mnhunter79]

check to make sure the battery is being charged when the motor is running. simmilar to the alternator in a car.

[RuKiddingMe]

Is the battery just shot, so bad that it won't hold a charge anymore.

But like mnhunter stated check to see if it is charging when running.

[TimR]

I'm more familiar with Johnson/Rude's, but Merc's have the same basic setup.

The stator will general an A/C pulse. The rectifier will convert that A/C current to D/C. The regulator (if there at all) will limit the output voltage to around 14 volts.

Is his tach working?

Tim

[marine_man]

TimR is right on - is his tach working? If it's not it's time for a recitifier.

The other thing you can do is put a multimeter on the battery. Measure the voltage prior to starting the engine, then start the engine and run it past half throttle - does the voltage pick up? If it doesn't, and you're sure the stator's still good, replace the rectifier.

marine_man