Kohler K91 Service Manual page 84

Troubleshooting G uide
1 5 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
Insert an ammeter In B+ lead from rectlfler- 1 .
1 .
regulator. With engine running at 3600 RPM
and B+ lead connected, measure the volt-
age from Bt (at terminal on rectlfler-
regulator) 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 .
"NOT E : Turn on lights , If 60 watts or more .
Or place a 2 . 5 ohm , 1 00 watt resistor
across battery terminals .
No
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 resls-
tance across stator leads using an ohmme-
ter.
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
Continuously
voltage from Bt lead to ground using a DC
Charges At voltmeter.
High Rate
8. 1 4
no loa d . Battery must be fully charged .
-
Test Conclusion
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 ) .
I f voltage I s 2 8 volts or more , stator Is O K .
2 .
Rectifier-regulator Is faulty . Replace the rectl-
fler-regulator.
If voltage Is less than 2 8 volts, stator Is probably
faulty and should be replaced. T est stator fur-
ther using an ohmmeter (test 3 ) .
3a. If resistance Is 0 . 1 /0 . 2 ohm s , the stator Is OK .
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) .
I f resistance (or continuity ) I s measured , the
stator leads are shorted to ground . Replace
stator .
1 . I f voltage I s 1 4 . 7 volts or less the charging sys-
tem Is OK. The battery Is unable to hold charge.
Service battery or replace as necessary .
If voltage Is more than 1 4 . 7 volt s , the rectlfler-
regulator Is faulty . Replace rectifier-regulator.