Normal voltage output from alternator?

[mr_mk4]

Hey,

I just replaced a faulty 90amp alternator on my 2004 New Beetle Cabrio w/2.0L 8V BGD engine with a new 120amp. Before the alternator put out around a low 14.10 volts at idle with nothing but the engine running (no lights...ect) and with this new one at idle it hover around 14.70 volts. Does that seem a bit high?

Thanks

[red99]

The Bentley manual says that at idle the voltage

"should be roughly between 13.8 and 14.5, depending on temperature and operating conditions. If the voltage is much higher than 14.5 volts, the voltage regulator is most likely faulty."

I would say that 14.7 is on the edge of "much higher." Why don't you try checking the idle voltage again after driving several miles so that the battery is fully recharged and everything is warmed up. See if it goes down some.

[mr_mk4]

Originally Posted by red99

The Bentley manual says that at idle the voltage

"should be roughly between 13.8 and 14.5, depending on temperature and operating conditions. If the voltage is much higher than 14.5 volts, the voltage regulator is most likely faulty."

I would say that 14.7 is on the edge of "much higher." Why don't you try checking the idle voltage again after driving several miles so that the battery is fully recharged and everything is warmed up. See if it goes down some.

I had the battery on a automatic trickle charge while it was out of the car during installation of the new alternator. Upon hooking up the battery it had a a charge of 12.8 volts.

[red99]

Originally Posted by mr_mk4

I had the battery on a automatic trickle charge while it was out of the car during installation of the new alternator. Upon hooking up the battery it had a a charge of 12.8 volts.

That is right at the upper limit of what a battery's voltage should be. It could cause the idle voltage to be at the upper limit as well. I still say drive it some and check it at idle again. You won't damage anything until you get to 15.5-16 volts.

[mr_mk4]

Alright I'll take it out and see what happens