generator weirdness

[Ralph L. Fullenwider]

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
>
>