generator weirdness

[pattypape]

On our 88 FC , the Onan has an alternator, it charges the battery
when the Onan is running. This is easy to check with a volt meter.

The generator battery is also charged by shore power or the 3208
alternator. The diode that Ralph mentions is located behind the entry
steps( on our 88 FC), It is a hefty fat diode , I would guess at
about 80 amps. There is also an automotive type fuse link, next to
these parts is the Aux Battery solenoid to tie all batteries together
for weak battery starting. All located center coach behind the step
near the leveler reservoir tank and motor.

There is also a relay in the left side front load center, that is
energized with 12 volts to latch these charging circuit together,
when on shore power or 3208 alternator charging, This circuit is
also fused with a glass automotive fuse. So check this circuit.
This could be a trouble area.
It is a good idea to check the age and load test all batteries
before replacing.

Bill 88 FC Michigan/Florida


--- In WanderlodgeForum@yahoogroups.com, "Ralph L. Fullenwider"
wrote:
>
> I don't have a charging print for a PT off hand, so this is from
memory.
>
> Unlike the '84/'85FC's which have a 160 amp battery isolator, the
PT
> usually had a large diode rectifier located in the gen set battery
circuit.
> The diode allowed voltage to pass from the alt or charger but not
back,
> ergo isolated. The out put side of the gen set battery follows the
usual 2
> solenoid pattern for the battery tie switch. Two of the solenoids
are under
> the entry door step and the third is usually found in the gen set
> compartment on the curb side wall, near the breaker box for the gen
set.
> Also in the '84, there was not an alt. installed on the Perkins for
> charging. The second solenoid in the gen set compartment was not
installed
> on all PT's it is also an isolation circuit.
>
> So, going from the above, here is a list of "might be's"
> 1. The Diode is bad, not allowing the gen set battery to charge.
(usually
> located under the drivers side front behind the bumper area)
> 2. The charger side of the inverter is not hooked up to the gen set
battery
> to charge when the gen set is running
> 3. The tie solenoid contacts are welded together.
> 4. Or as Jay mentioned, there is a high resistance short in the
cable some
> where.
>
> There are a couple of other things I have seen happen but they are
rare so
> won't go there right now.
>
> Would help to have a PT schematic of an '84 or '85 PT to trace out.
>
> Ralph
>
>
> At 11:45 PM 12/22/2006 +0000, you wrote:
> >dave Hardy- 84 PT40, his generator, while running will not charge
his
> >generator battery. The inverter on the coach is no help. He can
put an
> >aux battery charger on the generator battery and the generator
will run
> >from now on- without that the voltage drops and she dies. Anyone
have
> >ever have the same problem? How about a fix? Thanks, Ernie-83PT40
in
> >Texas- my generator just leaks diesel- no problem there
> >
> >
>