Installation manual

ALTERNATORS TESTING/TROUBLESHOOTING
. BATTERY
TESTING THE
OUTPUT CIRCUIT
ENGINE RUNNING
TO STARTER
SOLENOID
TESTING THE EXCITATION CIRCUIT
1. Connect the positive (+) multimeter probe to the
excitation tenninal R on the alternator and the negative
(-) probe to the ground terminal E on the alternator.
2. 'furn the ignition switch to the on position and note
the multimeter The reading should be 1.3 to
2.5 volts (see
EXCITER
TERMINAL
GROUND
TERMINAL
3. If the reading is between .75 and 1.1 volts, the
rotor field circuit probably is shorted or grounded.
4. If the reading is between 6.0 and 7.0 volts, the rotor
field circuit probably is open.
5. If no reading is obtained, an open exists in the
alternator-excitation lead or in the excitation circuit of
the regulator. Disconnect the lead from exc. terminal R.
Connect the positive multimeter probe to the excitation
lead and the negative multimeter probe to ground
terminal E. If the multimeter now indicates an
approximate battery voltage, the voltage regulator is
defective and must be replaced. If no voltage is
indicated, check the excitation circuit for loose or dirty
connections or damaged wiring.
CHECKING THE SERVICE BATTERY
Check the voltage of the service battery. This battery should
have a voltage between 13 and 14 volts when the engine is
running. If not, there is a problem in the service battery
charging circuit. Troubleshoot the service battery charging
circuit by checking the wiring and connections, the solenoid,
isolator, battery switch, and the battery itself.
When the problem has been solved and before the alternator
is back in operation, take the time to tighten and clean the
tenninal studs. Also clean the connecting terminals from the
wiring harness.,
ALTERNATOR REPAIR
If tests indicate a failed altemator, it will need to be
disassembled and repaired. Any good allemator service
shop can do the job.
NOTE: WESTERBEKE'S Service ManuallUlS detailed
instructions for the disassembly and repair of their
standard altem.ators.
BATTERY CARE
The minimum recommended capacity of the battery used in
the engine's 12 volt DC control circuit is 600-900 Cold
Cranking Amps (CCA).
Review the manufacturer's recommendations and then
establish a systematic maintenance schedule for your
engine's starting batteries and house batteries.
• Monitor your voltmeter for proper charging during
engine operation.
• Check the electrolyte level and specific gravity with a
hydrometer.
• Use only distilled water to bring electrolytes to a proper
level.
ii Make certain that battery cable connections are clean and
tight to the battery posts (and to your engine).
~ WESTERBEKE
Engines & Generators
33