Alternator Playing Up? - Help!

[Lamby22]

Hey guys,

Alternator left me stranded at a mates place with a flat battery, jump started and after that did the same thing again. Alternator wasn't changing, anyway the voltage regulator didn't have much "meat" left on them so we replaced that and the battery/alternator has been fine sice.

But, the batter light on the cluster still comes and goes. Got a level 3 cluster with volt readings and from what I can tell the light comes on from 12v-13v and when it finally decides to jump above 13v the light disappears. Any idea on what I can check? So basically my problem is the alternator not holding correct charge..

Cheers

 

[db_notso]

so the two regulator spring arms were worn away?
and now it doesnt charge effectively?

sounds like you have a fault in the regulator itself OR one of the diodes is playing up recomend going to auto electricians
and get them to bench test your altenator to check its internals
and when they say its stuffed then you can get an exchange one while your there~!

 

[Lamby22]

Ahk, cheers. So take it to them out of the car?

Is there anything else I can check as a last resort before taking it there?

 

[db_notso]

well...
get a multimeter and check its not charging at 14 volts at idle
apart from that an altenator is an altenator and elecies are used to it
just ring em, drive there , have a smoke/ or a bat, and get your car back~!

 

[Lamby22]

Yeah, I got a multimeter what wires do I test from? Wheres each lead on the multimeter go to?

 

[db_notso]

put multimeter on volts
have car running
put red on positive battery post
black on negative battery post
should read about 14 volts
if is reading low and you hold the revs higher and it reads 14 volts likely the regulator or diodes are shagged or windings are shorted (like if you hose it like coil packs)

 

[Lamby22]

Turns out some wire that runs to the positive terminal was shagged... fixed that up and charging at 14v-14.4v perfectly now. Running like a dream!

Cheers

 

[db_notso]

old fault altenator power harness~!
other symptoms are on cold start after a minute or so
very hot altenator and cold engine...

 

[Lamby22]

Yeah loose wire musn't have been making enough contact as occasionly revving it higher the light would go away, same with up hill etc..

Ah well end result is a working alternator so im happy!