Kohler — Carburetor Low Idle Fuel Adjustment
Adjustments
From a Kohler service manual covering: CH18, CH20, CH22, CH23, CH25, CH620, CH621, CH640, CH641, CH670, CH680, CH730…. Check it applies to your exact model before use.
Applies to: Kohler CH18
Before you start
- Do not attempt to remove limiter caps.
Procedure
- Place throttle control into idle or slow position; adjust low idle speed to 1200 RPM.
- Turn low idle fuel adjusting needle out (counterclockwise) until engine speed decreases (rich); note position.
- Turn needle in (clockwise) until engine speed decreases (lean); note position.
- Set adjusting needle midway between rich and lean settings.
- Repeat for other low idle adjustment needle on two-barrel carburetor.
- Recheck/adjust low idle speed to specified setting.
Tools required
- tachometer Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Low idle speed 1200 RPM (± 75 RPM)
Source: Kohler service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.