Spdtmhc Voltage Regulator Rectifier for Kohler CH/CV/ECH/ECV Engines — Direct-Fit Kit with Cable & Gasket

Spdtmhc 25-403-39-S voltage regulator rectifier — a direct-fit electrical replacement designed to restore proper charging and stabilize electrical output on compatible Kohler and Toro small engines.

This replacement rectifier/regulator is engineered to match the electrical connections and mounting of many Kohler CH, CV, ECH and ECV series engines and select Toro zero-turn models. It arrives as a complete kit with the regulator, cable, gasket and mounting screw so you can swap it in without sourcing extra parts. The unit is sold under compatible replacement numbers including 25-403-29-S, 25-403-32-S and 25-403-05-S, and it’s tested before shipping to ensure fit and function.

Will this regulator work with my Kohler engine model?

If your engine is one of the listed Kohler CH, CV, ECH or ECV series, this Spdtmhc regulator is designed to be compatible. Double-check the engine model stamped on your engine housing and compare it to the compatibility list below before ordering.

• Compatible Kohler models: CH11–CH26, CH620–CH1000, CV640–CV750
• Also fits Kohler ECH and ECV series such as ECH630–ECH980 and ECV650–ECV980
• Cross-references: 25-403-29-S, 25-403-32-S, 25-403-05-S and related part numbers
• Confirm engine model and mounting pattern for a correct match

How easy is it to install this replacement regulator?

Installation is straightforward for anyone comfortable with basic small-engine work: remove the old regulator, transfer the gasket and electrical connections, and secure the new unit with the supplied screw. The kit includes the cable and gasket so you won’t need additional parts for a standard swap.

• Kit contains: 1 regulator, 1 cable, 1 screw, 1 gasket
• Same mounting holes and connector style as original Kohler/Toro units
• Recommended tools: basic hand tools, voltmeter to verify charging after install
• Inspect wiring and connectors for corrosion before connection

What electrical and functional benefits does this regulator provide?

This rectifier/regulator converts AC from the stator to DC and controls charging voltage to keep battery and electrical systems stable. Replacing a failing unit helps prevent overcharging or undercharging and can resolve dimming lights, weak starts or electrical inconsistency.

• Regulates charging voltage to protect battery and electronics
• Converts alternator AC output into usable DC power
• Helps correct common symptoms of a faulty regulator like flickering lights
• Pre-shipment testing reduces likelihood of dead-on-arrival issues

Which machines besides Kohler will accept this part?

In addition to Kohler engines, this part fits select Toro zero-turn mower models that share the same electrical and mounting configuration. Always verify the Toro model number and compare part references against your machine’s parts manual.

• Listed Toro fitment: zero-turn mowers model 74255
• Cross-check part numbers: includes several 25-403-series replacements
• Suitable where mounting and connector type match original equipment
• Useful when OEM parts are superseded by cross-reference numbers

Who is this for: This Spdtmhc 25-403-39-S replacement is aimed at lawn care professionals, landscapers and DIY small-engine technicians who need a reliable, ready-to-install regulator for Kohler CH/CV/ECH/ECV engines or for the specified Toro zero-turn model. Buy it if you want a tested replacement that includes the necessary hardware and minimizes downtime for engine electrical repairs.