Alternator Not charging battery!

[CommoBloke]

Soo, I Have a 96' VS Series 3 Ute, standard 3.8l ecotec 5spd manual, swapped my Crf450r for it, got it and it needed a new engine so I proceeded to do an engine swap with a spare engine I had in a paddock bomb up the back, (also replace every Gasket and seal in engine) prior to the swap, the charging system worked great, but when I swapped it over, it isn't charging the battery, I have checked to wiring system over and over and can't find a flaw, checked all fuses, checked brushes on the alternator and they're fine, even replaced alternator, still no charge, don't know what it could be! Please help, I'm stumped,
Cheers, Zac

 

[hako]

May sound stupid but I once installed the battery wrong way round - double check!
Also if you have a multimeter check thicker cable from alt back to battery as it can break internally as the wire gets brittle and crystallises then breaks internally. Check smaller charge wire on alt has 12v when engine running.
Good Luck.

 

[CommoBloke]

Hey mate, thanks for the reply, I have already checked over the wiring 3 times now, battery is in the correct position, not sure what it is, when the engine was In the other car, it was charging and putting out 13.9v or thereabouts as it should be, now I check the voltage and it's on 0.5v, definitely not the brushes, they're in good condition, I checked the smaller wire off the back of the alternator(the one that goes to the battery with the clip) and it's only putting out 0.5v. Starting to think the brushes may be sticking, might have to give it a Tap while it's running and see if the voltage spikes. :/
Cheers

 

[Jxfwsf]

Is the alternator light in the dash lighting up? If it's blown the alternator won't start charging.
The Sense wire in the alternator doesn't output voltage, it detects the battery voltage so the wire/plug should be at battery voltage, if this isn't then it won't start charging.

 

[MYVESSV8]

little 3 or 2 watt bulb I think, the brush pack could stuffed, diode stuffed, with no output but .5v I would look at brush's, rectifier, and a voltage input source open circuit

 

[hako]

Re battery, you said "battery is in the correct position, not sure what it is, when the engine was In the other car," which could still mean the polarity is reversed as people will fit different battery types which have terminals swapped. Just check it is negative earthed.

Good Luck.

 

[CommoBloke]

Ok so today, I have checked the bulb in the cluster, changed it just for precaution but still no battery light when ignition is turned on(bulb is fine), have taken the alt out and checked the brushes, also cleaned contact points inside alt with fine emery paper, I am going to run another charge wire to the alternator from the battery.
Also swapped battery incase of reversed polarity.

 

[crazybiker]

Throw a multi-meter on the battery and see what voltage you've got. Then put your air-conditioner on, and put every light you can on (including high beams).

Check the voltage again whilst maintaining the revs at about 1200-1500RPM.

If you're voltage is low at this point, and/or decreasing, then you've dropped a phase in your alternator.

 

[hako]

Apologies if I seem to be 'harping' on this but can you confirm that the battery negative terminal goes to earth. You said: "Also swapped battery incase of reversed polarity. That still does not confirm that the battery polarity is not reversed.
Battery negative terminal must go to earth.

Good Luck.

 

[CommoBloke]

Sorry, yes negative terminal is earthed correctly. Before I swapped batteries I was using another battery and jump cables to start it as the battery in it was dead, and when I removed the cables the engine would die, I rewired the alternator cables today and I removed the jump cables and it didn't die instantly like it did previously, took about 5-6 seconds before it died. Also the sensor wire is now picking up battery Voltage. I put a multi meter on it and it is still dropping voltage while running. Might go to the wreckers on Monday and get another alt.

Appreciate all the help and input guys.