Kohler — Cylinder Leakdown Test (Dual Gauge Test Procedure)

Testing & diagnosis · Engine

From a Kohler service manual covering: 14690-12, CV173, CV200, CV224. Check it applies to your exact model before use.

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Procedure

1. Run engine until oil temperature reaches and maintains 150°F (66°C) or more for a minimum of 5 minutes under normal load.
2. Remove spark plug(s) and air filter.
3. Rotate crankshaft until piston of cylinder being tested is at TDC of compression stroke and hold in position.
4. Connect an air source (at least 100 PSI) to tool.
5. Turn regulator knob clockwise; confirm both gauges read approximately the same air pressure from 0 to 80 PSI; release pressure before proceeding.
6. Install adapter hose into spark plug hole (use 12 mm x 14 mm adapter if required).
7. Firmly hold engine at TDC; connect adapter hose to tool quick connect; turn regulator clockwise until left gauge reads 20 PSI.
8. Slowly turn regulator knob clockwise until left hand gauge maintains selected test pressure (80 PSI for engines over 200 cc or high leakage at 35 PSI; 35 PSI for single cylinder walk-behind push mower
9. Compare right gauge reading to Test Pressure Chart to identify percentage of leakage; refer to Leakdown Test Results chart for action.
10. For leakage in yellow or red zone, repeat test procedure after operating engine under normal load; confirm piston at TDC.
11. Turn pressure regulator knob to zero (counterclockwise) after each test to prevent gauge damage.

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.

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