B
Brian Stirling
Guest
I just purchased a 1990 Pace Arrow motor home and discovered a problem
with the Onan GenSet. The first night I tried to start it it wouldn't
start -- slow turn over. This morning I hooked up a DVM to the
batteries and it was about 12.03V without any load and with the shore
power and generator off. When I tried to start the generator it did
the slow turn over thing and when I checked the DVM I found the
voltage had dropped to about 8.5V during the attempt (DVM set to
record min/max). I then hooked up the shore power and 30 minutes
later I was able to start the generator without much problem. I
disconnected the shore power cable and went to the store to get some
engine start spray for future use. When I returned about 45 minutes
later I found the voltage at the batteries was over 16.6V. This is
not good!
I then looked through the manuals that came with the Pace Arrow and
found a schematic that is a bit confusing. I can see a reference for a
voltage regulator (VR1) and there is also a little board with the
rocker start/stop switch and on that board is a diode looking device
labeled (VR1). The VR1 on the board does not look beefy enough to be
the unit controlling the field coil on the generator so I have to
presume the real voltage regulator is NOT on the little board --
right?
One more thing, if I have the generator running and the batteries are
driving up towards 16+V if I turin off CB1 the voltage indication at
the batteries drops right down. I would not think there is a separate
AC powered charger being driven by the generator in addition to the
one that seems to work just fine when power by shore power.
Wait a minute, I found another manual (Parts Manual) that indicates
there are three different revs of board (300-3056, 300-3484-01, and
300-3687-01) that is referred to as (Board, Printed Circuit) with the
300-3056 specified as (Without Capped AVR Regulator), 300-3484-01 as
(With Capped AVR Regulator) and 300-3687-01 as (Single Phase - Begin
Spec G). In addition, there is also a part called (Regulator,
Voltage) and there are two part numbers listed (305-0809-01 = 60
Hertz) and (305-0809-03 = 50 Hertz).
I would guess that the voltage regulator on the little board is for
the DC charging and the other voltage regulator, either 50 Hertz of 60
Hertz is for the AC voltage regulation -- right?
If this is so then I probably need to replace the little board. If so,
which version of the board should I get? The board that was in there
has two numbers on it. On the silk screen is (332-3112.A) and on a
label with what looks like a barcode is the number
(300-3763-01-FS-0186156G16). If I read this correctly the board is a
(300-3763-01) and that does NOT match any of the three listed in the
manual.
Here's the full info for my GenSet:
Onan Emerald III GenSet
Model#: 6.5NHEFA26100G
Serial#: B900298288
If anyone can recommend a coarse of action here I'd be very thankful.
Thanks,
Brian Stirling
with the Onan GenSet. The first night I tried to start it it wouldn't
start -- slow turn over. This morning I hooked up a DVM to the
batteries and it was about 12.03V without any load and with the shore
power and generator off. When I tried to start the generator it did
the slow turn over thing and when I checked the DVM I found the
voltage had dropped to about 8.5V during the attempt (DVM set to
record min/max). I then hooked up the shore power and 30 minutes
later I was able to start the generator without much problem. I
disconnected the shore power cable and went to the store to get some
engine start spray for future use. When I returned about 45 minutes
later I found the voltage at the batteries was over 16.6V. This is
not good!
I then looked through the manuals that came with the Pace Arrow and
found a schematic that is a bit confusing. I can see a reference for a
voltage regulator (VR1) and there is also a little board with the
rocker start/stop switch and on that board is a diode looking device
labeled (VR1). The VR1 on the board does not look beefy enough to be
the unit controlling the field coil on the generator so I have to
presume the real voltage regulator is NOT on the little board --
right?
One more thing, if I have the generator running and the batteries are
driving up towards 16+V if I turin off CB1 the voltage indication at
the batteries drops right down. I would not think there is a separate
AC powered charger being driven by the generator in addition to the
one that seems to work just fine when power by shore power.
Wait a minute, I found another manual (Parts Manual) that indicates
there are three different revs of board (300-3056, 300-3484-01, and
300-3687-01) that is referred to as (Board, Printed Circuit) with the
300-3056 specified as (Without Capped AVR Regulator), 300-3484-01 as
(With Capped AVR Regulator) and 300-3687-01 as (Single Phase - Begin
Spec G). In addition, there is also a part called (Regulator,
Voltage) and there are two part numbers listed (305-0809-01 = 60
Hertz) and (305-0809-03 = 50 Hertz).
I would guess that the voltage regulator on the little board is for
the DC charging and the other voltage regulator, either 50 Hertz of 60
Hertz is for the AC voltage regulation -- right?
If this is so then I probably need to replace the little board. If so,
which version of the board should I get? The board that was in there
has two numbers on it. On the silk screen is (332-3112.A) and on a
label with what looks like a barcode is the number
(300-3763-01-FS-0186156G16). If I read this correctly the board is a
(300-3763-01) and that does NOT match any of the three listed in the
manual.
Here's the full info for my GenSet:
Onan Emerald III GenSet
Model#: 6.5NHEFA26100G
Serial#: B900298288
If anyone can recommend a coarse of action here I'd be very thankful.
Thanks,
Brian Stirling