Mercruiser charging system..

[SabineStalker]

Hello, I have a question about the charging system on my boat. Its got twin Mercruiser 165's. Im not sure the volt guages are working, and I dont think the alternators are putting out either. How can you check the alternators to see if they are charging. they are 1 wire alternators. Thanks.

 

[mdcan5]

Re: Mercruiser charging system..

If you can remove the alternators, many auto part stores have a machine to test them. Also you may consider replacing your voltmeters with ampmeters. They give a much better indication of how the alternators are performing. Good Luck!

 

[echozulu]

Re: Mercruiser charging system..

its odd if both alternators went out unless you sunk it. just take black probe of a voltmeter put it on the negative [ - ] terminal of the battery the red probe on the other. have neighbor crank engine and look at the voltmeter to see if the voltage is higher than when the neighbor popped the top of YOUR last beer

 

[Monte Cryts]

Re: Mercruiser charging system..

The easiest way to test if you have output on the alternator is to start the engine and then unhook the batery. If the engine stays running then the alternator is more in likly good.<br />To properly test the alternator start the engine and then put a clamp on dc current meter around the big positive wire on the alternator. Should have a current draw. Remember there must be a voltage present to the alternator before it will work.