Simplicity Replacement Engine — Kohler CH640-3126 20.5 HP Command PRO Horizontal Engine Click to zoom

Simplicity Replacement Engine — Kohler CH640-3126 20.5 HP Command PRO Horizontal Engine

MPN ENGINE

In stockReplacement Engine

Overview

🚚 Flat-rate LTL freight: $200
Ships palletized by LTL freight to the lower 48 states + DC for a flat $200. Need it fast? Choose Expedited or Need It Fast ($235.95) at checkout and we'll call you with the fastest options.

Need a replacement engine for your Simplicity equipment? This is a brand-new, genuine Kohler CH640-3126 (Rehlko spec PA-CH640-3126) 20.5 HP Command PRO horizontal-shaft engine with a 1-1/8" x 2-3/4" crankshaft — the engine spec used on Simplicity machines.

Kohler Engines now operates as Rehlko; same engine, same factory, same part number. Ships new in the crate with the manufacturer's engine warranty.

Before you order: confirm fitment

  • Check the engine tag on your Simplicity machine: it should read CH640-3126 / PA-CH640-3126 or an older spec this engine replaces (CH640-3110).
  • Match crankshaft diameter and length, mounting pattern, PTO/clutch, fuel and wiring connections.
  • Not sure which engine your machine has? Call (646) 666-7225 with your machine model and serial number and we'll confirm the right spec.

Engine specifications

Manufacturer Kohler (now Rehlko)
Part number (MPN) CH640-3126
Rehlko spec number PA-CH640-3126
Series Command PRO
Gross power 20.5 HP
Displacement 674 cc
Cylinders V-twin, OHV
Crankshaft orientation Horizontal
Crankshaft 1-1/8" x 2-3/4"
Fuel system Carbureted gasoline
Starter Electric Start
Charging 15 Amp
Oil capacity 2.0 qt (1.9 L)
Muffler Not Included
Shipping weight 152 lb
Condition New, genuine OEM
Fits Simplicity

Frequently asked questions

What engine does the Simplicity use?

This listing is the Kohler CH640-3126 spec (20.5 HP). Always confirm against the tag on your existing engine.

How much is shipping?

Engines ship palletized by LTL freight for a flat $200 to the lower 48 + DC. Expedited / Need It Fast ($235.95) is available at checkout.

Is this the same engine as Kohler CH640-3126?

Yes — this is the same new Kohler/Rehlko engine sold on our Kohler CH640-3126 page, listed here by machine for easy lookup.