New alternator 15V+ on idle 12 on load :(

[BristolSam16v]

Just fitted a 2nd hand but gd nick (so i thought) alternator. Checked bushes before I put it in all looked fine.

Now on idle its over 15V but on load it drops right down to just over 12v? If I rev the engine it picks up and when im driving the windows are really fast (used to be shit slow on the old buggered alternator), any ideas what it could be? Someone on cliosport suggested the voltage regulator could be shafted? :(

[Swervin_Mervin]

I'm afraid I don't understand what the problem is. :?

[BristolSam16v]

Basically unless im revving the engine the light are really dim, the windows are slow and its only measuring just over 12v across the battery!

[Bailey_1260]

But isnt 12V good, 15V bad?

Is there anything else sucking up current? (amps, subs etc)

[BristolSam16v]

Well its around 15.75v on idle if i remember rite, which I think is good?

But on full load it drops rite down, ie on idle the windows go up and down really slowly, lights are dim etc etc soon as i rev it up high everything gets brighter, surely it shudnt be like that?

[BRUN]

ideal figures are 14.4v idle, 13.5v or above under load

[cliokiz]

Mine is the same mate, windows are slow unless i rev it a bit etc and lights are dim unless i rev it - always been like that on my valver engine and on my willy engine.

I think it's just the way they are! (Shit! :lol: )

[BristolSam16v]

Yeah looks like the regulator is shafted, its boiling my battery :(