Genuine Kohler Regulator Rectifier 20 to 30 amp, FW W/O, 25-403-48-S Free Shipping, No Tax.
Replaces: 2540349, 2540339-S, 2540305S, 2540305-S, 25-403-05-S, 2540308S, 2540308-S, 25-403-08-S, 2540320S, 2540320-S, 25-403-20-S, 2540321S, 2540321-S, 25-403-21-S, 2540329S, 2540329-S, 25-403-29-S, 2540332S, 2540332-S, 25-403-32-S
Photo is of the old style Regulator
This latest rectifier-regulator, has a ground lug and built-in over-voltage protection that
is self-resetting. The over-voltage protection prevents possible damage to other electrical components
if an engine is jump-started. This regulator is especially recommended for use on EFI engines, except
on Walker mowers where there is insufficient clearance for it to be used. When replacing an earlier
regulator, like part number 2540305S, just use the new regulator. To replace an older
regulator, which has short wire coming out of regulator use kit 24755144S, which includes the new regulator and the necessary conversion pieces.
**** If regulator does not fit you will need to modify the blower housing to make this fit ****
The protective circuit in the new regulator works much like a circuit breaker. If excessive voltage is
detected, the protective circuit breaks/opens the charging circuit (B+ output) to prevent the elevated
voltage from reaching other components. Excessive voltage can be due to spikes caused by attaching
or disconnecting jumper cables, or by loose battery terminal connections. It can also result from a
defective battery that is not capable of holding a charge.
Important Service Notes
Once the circuit has been tripped, the circuit will discontinue charging for approximately 20 seconds.
After 20 seconds the regulator will resume charging. If the over-voltage condition has not been
corrected, the circuit will discontinue charging for another 20 seconds. This condition will repeat until
the overcharge condition is corrected. Stop the engine. With the engine off, test voltage across the
battery terminals. If it is below 12 volts, use an auxiliary charger to charge the battery.
When the battery has been charged, start the engine and test to confirm that charging output has been
restored. Allow the engine to run for several minutes and test again. If the battery is defective, the B+
circuit will trip repeatedly until the faulty battery is replaced.