Kohler — Crankcase Vacuum Test with Manometer
Testing & diagnosis · crankcase breather system
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
Procedure
- Insert rubber stopper into oil fill hole; connect manometer with pinch clamp closed.
- Start engine and run no-load high speed.
- Open clamp; note water level.
- Engine side level should be minimum 10.2 cm (4 in.) above open side.
- Close pinch clamp before stopping engine.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Crankcase vacuum minimum 10.2 cm (4 in.) water
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.