Kohler — Cylinder Leakdown Test (Dual Gauge)
Testing & diagnosis · Cylinder/Piston/Rings/Valves
From a Kohler service manual covering: 1P14 690 11, XTX650, XTX675, XTX775. Check it applies to your exact model before use.
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Before you start
- To prevent damage to gauge assembly, always turn pressure regulator knob to zero after each test
Procedure
- Run engine until oil temperature reaches and maintains 150°F (66°C) or more for minimum 5 minutes under normal load.
- Remove spark plug(s) and air filter from engine.
- Rotate crankshaft until piston of cylinder being tested is at TDC of compression stroke and hold in position.
- Connect an air source (at least 100 PSI) to tool.
- Turn regulator knob clockwise; confirm both gauges read approximately the same air pressure from 0 to 80 PSI. Release pressure.
- Install adapter hose into spark plug hole; use 12 mm x 14 mm adapter if required.
- Hold engine at TDC, connect adapter hose to tool quick connect. Turn regulator until left gauge reads 20 PSI.
- Slowly turn regulator clockwise until left hand gauge maintains selected test pressure (80 PSI over 200 cc; 35 PSI single cylinder walk-behind).
- Compare right gauge reading to Test Pressure Chart to identify percentage of leakage.
- For yellow or red zone leakage, repeat test after operating engine under normal load and confirming piston at TDC.
Tools required
- Dual Gauge Cylinder Leakdown Tester Amazon
- Adapter 12 mm x 14 mm Amazon
- Holding tool Amazon
- 3/8 in. breaker bar Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
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.