Alternator

larryho · Post by **larryho** » Sat Apr 07, 2007 8:14 am

I just installed a 75 amp imternally regulated alternator to my 12V Beetle. which used to have a 51amp. With an air cond, night driving and a CD system, I thought a 75amp will be better.
My problem now is that after installation and the engine running at fast idle the indicator lamp (red light) do not go off. Only when I press the gas/drive off will the indicator light goes away.
I do not have this problem with the 51amp alternator and it seems that three of my friends who installed the 75 amp alternator has this same problem. Now at the traffic junction I have to press the gas pedal to ensure charging.
What have we done wrong and how can we rectify this.

Thanks.

seabluebug · Post by **seabluebug** » Sat May 05, 2007 5:02 am

Hi Larry - I can't help with this one since I have a 6 volt system but I do know that many of the VW's had the red light "Flicker" when at idle and it went off as soon as the car was in motion and that was considered "normal" - but that could have been specific to 6 volt - I can't remember. I would get a volt meter and check the voltage going to the battery during idle and see if it is anything to really be concerned about. Good luck! Perhaps you have solved your problem already!

larryho · Post by **larryho** » Wed May 09, 2007 5:49 am

Thanks. No I have not solve the Alternator problem. The electrician tested the voltage and it seems that the alternator is not charging at engine low speed. Perhaps its the internal regulator which is not working or the alternator itself is faulty. We have now change back to the 51amp and everything is normal. The voltage on the 51amp may not be enough and we really would like to have the 75amp in the car.

volksbugusa · Post by **volksbugusa** » Sun May 13, 2007 5:48 am

larry:
when you turn every power switch on at the same time does the charge
light remain lite.? Sounds like to much amps thru the system and no where to go.Are you on an old 6 volt wire system but converted?
volksbugusa

larryho · Post by **larryho** » Sun May 13, 2007 9:03 am

The charge light was there. As I said only at high speed will there be sufficient charge. Someone suggested to add a 10GA wire between the Alternator B+ terminal and the positive battery cable (at the solenoid). Yet to try. We had now change to the 51amp Alternator and everything is ok. The car was converted to 12V but I believe some of the wires had been changed to complement for this.
We have another car (6 to 12V) who fixed a 75 amp Alternator and he has no problem. Our electrician points to a faulty Alternator/regulator in this rebuilt item. We will however try the extra wire at a later date. Thanks for the input.