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Need New Alternator?

Penfold

By Penfold,
in General Maintenance

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Penfold Rising Star

Penfold

Posted
Posted

Hi,

Car - R33GTR (powerfc)

Just reporting on a problem I've been experiencing recently. Had the battery light come on during a fairly long drive and have since then been watching the voltages on my powerfc. Seem to be gradually dipping down from 12 volts when the light came down, right down to about 10.5 volts. However, this was happening pretty slowly. Decided to not drive the car for about 5 days to see what would happen. Went to start the car and didnt have enough juice - voltage was less than 10 volts. Hooked up the charger and showed the battery being pretty exhausted so left it on all night and filled right up. Went for a few drives over the next few days - volts when running went up to 14 volts for a few trips. Then gradually started going down again. Dropped down to about 11.8 volts again & the battery light came on so wacked on the charger again and showed that the battery was again pretty exhausted => recharged again.

Do you guys think its time for a new alternator?

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Moodles2 Grand Master

Moodles2

Posted
Posted

Terminals on both battery and the terminals themselves need a good clean and wirebrushing.

If you have a multimeter, fully charge the battery up. Take a voltage reading at full charge, then take the next reading the next day or so and compare. Battery shouldn't loose any voltage while sitting between readings, if it does then it needs replacing (or cells needs to be topped up with distilled water)

It's weird that you would loose voltage in the battery since everything is being powered by the alternator not the battery while driving.

t_revz Grand Master

t_revz

Posted
Posted

Brushes in alternator might be just about stuffed. If so it will fail completely soon. You could try next time the light is on give the back of the alternator a light tap preferably with wood and see if it comes good. Will need a freshen up if so

Penfold Rising Star

Penfold

Posted
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Posted

Cool, will give it a go.

Only got the battery a year ago - Delkor 22F-520FD.

Its weird because the battery is on 12 volts when I went to start it before several drives today. It does go all the way up to 14volts after driving for a bit so everything seems normal. But then it will slowly drop after a few days.

Thanks!

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