Charging problem (1 Viewer)

[madinal]

I just got back from Autozone and they said my alternator was fine. The problem was that the new battery died. I jumped it and checked the voltage at the battery at 1500 rpm. It was about 11.8 volts. Tomorrow I'll put the altenator back in but don't know what to do next.
Any suggestions on why the battery won't charge?

 

[fjwagon]

What is the voltage of the battery when it not running? Should see a difference in voltage between it being off and on. I would try Recharging the battery if it's too low. An alternator will maintian the charge but if it's too low your best is to charge it.

Here is something you can try to find out if your battery is draining: disconnect the negative terminal and connect a test light in series to complete the circuit. If the test light comes on, something is draining the battery. My first guess would be to look at the voltage regualator if it's external. Something else that is obvious but we sometimes forget is make sure you have clean terminals.

 

[MooseMarine]

I had a very similar issue about a month ago or so. I'll look for the threads and email you the links. I ended up having several issues. First off - check your wiring against a diagram. My PO had just about every wire hooked up incorrectly (even the ammeter wires were backwards!)

Check the continuity of your wires, especially between the alternator, the voltage regulator, ammter and battery.

Check your grounds - engine, frame, etc.. you might need to ground your alternator to the engine too. After I wired everything back up, I ended up replacing the alternator and voltage regulator (x2). The second regulator was a solid state unit from Auto Zone.

On a side note, I had AutoZone test my old alternator, and they said it was good too.

 

[MooseMarine]

https://forum.ih8mud.com/40-55-seri...-help-troubleshooting-electrical-problem.html

https://forum.ih8mud.com/40-55-series-tech/421032-electircal-problem-update.html

Look at bsmith123's reply in the second thread. The wiring diagram was perfect. Where in Alabama are you? BTW - happy 235th!

S/F

Moose

 

[madinal]

I'm up in Madison. I'll try out some of these things. It's getting closer to running but something always comes up.

 

[MooseMarine]

My in-laws live about 20 min from you. Next time I'm up there, I'd love to swing by and check out your 40.

 

[bsevans]

I have a CS144 Alternator with an internal VR and my experience with the output of the alternator is as follows: If my battery has a significant discharge the alternator will output as much as 14.7V. As the battery charges, the alternator slowly drops in output voltage until it stabilizes at 14.4V with a fully charged battery. If you are only getting just over 11V, I would look at the voltage regulator and also confirm that the alternator/VR is getting 12V for excitation when the ignition is turned on via the key.

You need to make sure the battery is good and does not have an internal short. A battery that is faulty can causes the alternator to continually output elevated voltage that can eventually cause the VR to fail and can damage the alternators diodes.
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