Well, each cell generates a little over 2v, but internal resistance usually
gives you 12v to 12.4v at the terminals.  Alternators are set to put out
between 13.6v to 14.2v at any rpm, but that can drop under load or at low
speed.  High speed should be at least 13.6v, if not, your alternator is weak
or too small for the load.  Vanagon Westies  should have a 90amp alternator,
but output will drop with age.

Sounds like you are due for a new one, or take yours to a good auto electric
shop for rebuilding.

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Woody Halsey
Sent: Saturday, July 19, 2008 12:55 PM
To: vanagon@GERRY.VANAGON.COM
Subject: proper voltages

Dear List,

Can anyone tell me what voltage readings I should be getting from my
battery:

1)     with engine off
2)     with engine idling
3)     with engine at high RPM (if I can figure out how to test that)

My mechanic states that since the readings do not go above 13V when the
engine is running, the alternator must be malfunctioning.  Is that true?

P.S.  My paint/rust/insulation/interior detailing projects are finally
completed. Of course I will never take it out of the garage again for
fear of getting wet, but she sure looks nice. My surgeon wife likens her
to an elderly lady with a face job: beautiful on the outside, but just
waiting for a key organ to cease functioning.

Thanks,

Woody