Kohler K91 Service Manual page 86

Trou bleshooting Guide
25 Amp Battery Charging System
" NOTE : Zero ohmmeters and voltmeters on each scale to ensure accurate readings . Voltage tests should
be made with engine running at 3600 RPM
Problem
1 . Insert an ammeter In
regulator. With engine running at 3600 RPM
and
age from
tor) to ground using a DC voltmeter.
If voltage Is 1 3 . 8 volts or more , place a
minimum load of 5 Amps " on battery to re-
duce Voltage . Observe ammeter.
" NOTE : Turn on lights , If 60 watts or more .
Or place a 2 . 5 1 00 ohm , watt resistor
No
across battery terminals .
Charge
2 . Remove connector from rectifier-regulator.
To
With engine running at 3600 RPM , measure
Battery
AC voltage across stator leads using an AC
voltmeter.
3 a . With engine stoppe d , measure the
resistance across stator leads using an
ohmmeter.
3b . With engine stopped , measure the resls-
tance from each stator lead to ground using
an ohmmeter.
Battery
1 . With engine running at 3600 RPM , measure
voltage from
Continuously
voltmete r .
Charges At
High Rate
8 . 1 6
no load . Battery must be fully charged .
-
Test
B+
lead from rectifier-
B+
lead connected , measure the volt-
B+
( at terminal on rectlfler-regula-
B+
lead to ground using a DC
Conclusion
1 .
If charge rate Increases when load Is applied ,
the charging system Is OK and battery was
fully charged .
If charge rate does not Increase when load Is
applied , test stator and rectifier-regulator
(tests 2 and 3 ) .
2 . I f voltage I s 2 8 volts o r more , stator I s O K .
Rectifier-regulator Is faulty. Replace the rectl-
fler-regulator .
If voltage Is less than 28 volt s , stator Is prob-
ably faulty and should be replaced . Test stator
further using an ohmmeter (test 3 ) .
3a. If resistance Is 0 . 064/0 . 096 ohm s , the stator Is
O K .
If resistance Is Infinity ohms, stator Is open .
Replace stator.
3b . If resistance Is Infinity ohms (no continuity) the
stator Is OK ( not shorted to ground ) .
If resistance (or continuity) Is measured , the
stator leads are shorted to ground . Replace
stator.
1 . If voltage Is 1 4 . 7 volts or less the charging
system Is OK. The battery Is unable to hold
charg e . Service battery o r replace as neces-
sary.
If voltage Is more than 1 4 . 7 volt s , the rectlfler-
regulator Is faulty . Replace rectifier-regulator.