JoeSimcoe@aol.com wrote:
> OK, so I am going to show my ignorance now.
> I have an alternator that is overcharging - in the red 15+
> volts on the gauge.
> What would cause an alternator to OVERcharge?
> Bad internal dohicky?
> Can I get this tested without pulling it off the car?
Joe,
My guess is that the regulator in the alternator is
probably no longer working, allowing the alternator to put
out 15+ volts.
The first thing to do, however, is to use a voltmeter to
verify that the problem is the alternator, and not the gauge.
If you don't have a multimeter, beg, borrow, or buy one. Note,
an excellent digital multimeter (DMM) is nearly as important
for an LBC owner as a set of combination wrenches -- I have one
in my trunk toolbox. The alternator output at engine RPM of
about 1200+ should be between say 13.5-14.5 volts.
If the meter also indicates 15+ volts, you most definitely
have a faulty regulator. This can be replaced independent
of the rest of the alternator. You have a number of possible
fixes:
1) Easiest -- Take the whole alternator off, and use it as
a core for a whole new one. This is overkill in this case,
but is simple, fast, and easy -- whilst being expensive.
2) Medium -- Take the whole alternator off, take off the
cover, and replace the regulator. You'll probably need to
order a replacement regulator from TRF, Moss, VB, etc., or
you may be able to find a local one. (Note, make sure
the connections to the regulator were all good before going
to the hassle of replacing it...)
There is an article by Charlie Brown on alternator diagnosis
and repair on the VTR site, you may want to take a look at this
to get a better feel for what is probably going on.
http://www.vtr.org/maintain/alternator-repair.html
3) Hardest -- This is the same as step 2, except since you
have the alternator cover off, you may as well clean up
the various contacts, resolder any weak connections,
replace any wiring with insulation, and bead-blast the
alternator cover. Actually, the alternator mounting
bracket may need a bead blasting too. While it's off, you
may as well replace the fan belt. For that matter, the
fan belt drive pulley on the crankshaft may need bead
blasting... When removing the pulley, you may find that
there is a little more play there than is good, and that
you should really replace the thrust washers, but while
you're doing that it would be a good time to rebuild
the engine, and paint the engine bay, and scrape that
rust off the frame, and...
--ken
VTR WWW Maintainer -- http://www.vtr.org
'74 TR6 Daily Driver
--
Kenneth B. Streeter | EMAIL: streeter@sanders.com
Sanders, PTP2-A001 |
PO Box 868 | Voice: (603) 885-9604
Nashua, NH 03061 | Fax: (603) 885-0631
|