Dead Alternator, or.. ?

[hedonist]

Hi again,
I just posted in the wheels, tyres & brakes forum regarding our spongy brakes. As luck would have it, that's not the only problem we're experiencing...

We're having an intermittent issue with the charging system. A while back we noticed that the battery got really weak and just gave up one day. Charged it and tested it and the battery itself seems fine and hold its charge well enough. But when the engine is running, the voltage on the battery terminals was just 12.1V or so; so it wasn't getting charged. Then later, mechanic checked it and it measured higher so he tells us it's fine and after we pay the bill and drive it home, again the same issue; 12.0-12.1V with the engine running, even when you rev it.

Would the alternator be at fault? Or could it be something stupid & simple (cheap!) that should be checked first?

We have been taking it offroad into quite deep mud and water as well, could this kill the alternator? Is there a way of protecting it somehow?

Thanks for your help!

Laura

[Darrell]

It should be about 14v when running so it sounds like its not charging.
Yes offroading can allow dirty water inside, which can make the brushes stick.
A good wd40 can help beforehand but to be honest if you drive in deep muddy water its going to happen.
Sometimes a dam good hose can clean it out or give it a strip-down and clean before spending out on a new one.

[hedonist]

Thanks Darrell, yeah 14v is what we thought. Will try wd40 before the next time we take it off road, and cleaning it out better if we end up in muddy water...

In the end we got a reasonable deal from the local mechanic for a new alternator, apparently after he tested it, he figured out that the relay was gone.. fingers crossed this one lasts!

[turbo-tom]

with my alternator i give it a good blast with the jetwash okay its not ideal but it hasnt harmed it yet and i give it a good splash of wd before and after i go off roading

[suzukisteve]

dont forget to check the tension and condition of the alternator belt itself. if wet and dirty it can slip and cause the alternator to not charge properly