you could..
that's the easiest and cheapest thing to try.

you could also buy an adjustable solid state voltage regulator/brush
package for a Bosch alternator.

the guy that turned me onto those...a starter/marine/alternator
rebuilding shop ..set his at 14.5 volts.

On 1/21/2014 4:54 PM, Don Hanson wrote:
> Inline Vw motor, digifant electronics.  Same alternator as Vanagon, etc.
> This alternator is about 4 yrs old now, sourced from Van Cafe. It has been
> worked hard keeping 2 batteries charged through extensive prolonged
> off-grid camping. I've gone through 3 standard starting batteries, often
> draining the auxiliary battery charging electronics, etc.
>
> Today my aux battery was low so I plugged my 12v power source for my lap
> top into a power point that's wired to the engine battery.  The laptop's
> battery was dead, but I figured the bigger engine battery would have the
> juice to charge the computer and still fire up the van. Wrong, the laptop's
> battery took most of the charge from the van.  Tried jumping.from the coach
> battery but that one was dead, too.  Did a one-man push start and drove
> around for half hour.  Starts right up again, but I put my multimeter
> across the vehicle main and it reads just 13.2v engine idling with no
> accessories on.  Pretty low, according to Bentley.  Would that be
> Reg/brushes ? in that time span and the use cycle?
>
> Is the test just to get some new brushes and stick em in, then check the
> battery input again?
>
> Thanks, Don H.
>