Westerbeke 55B-FOUR - Troubleshooting

DUAL OUTPUT ALTERNATORS
BALMAR REGULATOR
TROUBLESHOOTING
NOTE: Before troubleshooting, make certain that the drive
belts are tight and the batteries are in good condition.
Regulator Testing
The red "battery sensing" wire A connects to the battery, it
must
always read battery voltage. If battery voltage is not
present, trace the wire for a bad connection.
The
white wire S should read 0 volts with the key off, 12
volts [approximately] with the key on. If the readings are
incorrect, trace the wire for a bad connection.
The blue wire F supplies current to the alternator fields, its
voltage will vary depending on the battery charge or actual
load/rpm. The readings can vary from 4 to 12 volts with the
key on, 0 volts with the key off.
KEY ON • NO VOLTAGE REGULATOR IS DEFECTIVE
KEY OFF· BATTERY VOLTAGE REGULATOR IS DEFECTIVE
REGULATOR TEST POINTS AND PROPER VOLTAGE
•
Ignition Off
1
Ignlllon On Terminal/Color Engine Running'
I Brown
Dvolts 2 ·12 volls 14.2 volts
A Red
12.6 volts 12 volls 14.2 volts
S While
o volts o volts 6·8 volts
F Blue Ovolts
10 ·11 volls
4·12volts
All. Oulpul 12.6 volts
12 volts
14.2 volls
Alternator Testing
The regnlator Is functioning properly and the batteries
are in good condition. .
1. Test the voltage at the alternator plug with the engine
off-key on. The
voltage at the alternator terminal F and
the voltage in the plug [blue wire F] from the regnlator
should read the same.
2. Hold a screw driver close [1/2"] to the alternator pulley.
If voltage is present you should feel the magnetic field. If
not, the problem may be the brushes [worn] or the rotor
[open circuit].
3. Start the engine, at fast idle the output ternrinals should
indicate
14.2 volts [no load]. A reading of 12.6 would
indicate the alternator
is not performing properly.
Apply a load such as an electric bilge pump, the voltage
should maintain at least 13.8 volts. 13 volts or less
indicates the
alternator is faulty.
NOTES:
o When the engine is first started, it takes a lew moments
for the alternator to "kick in" and take the load fa
noticeable change in the sound of the engine J.
o A slight whine from the alternator when the load is
normaL
o When the alternator is producing high amperage, it will
become very hot.
o When replacing the alternator drive belts, always
purchase and replace dual belts in matched pairs.
NOTE: For additional information on regulators and
alternators, contact www.BALMAR.COM.
~ WESTERBEKE
Engines & Generators
328