John Deere — Check and Adjust Valve Clearance Serial Number ( —199,999)
Adjustments · Cylinder head and valves
From a John Deere service manual — check it applies to your exact model before use.
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Before you start
- To prevent accidental starting, always disconnect NEGATIVE (—) battery terminal.
- Valve clearance MUST BE checked and adjusted with engine COLD.
Procedure
- Remove rocker arm cover with ventilator tube.
- Install flywheel turning tool and timing pin.
- Rotate engine until timing pin engages timing hole and No. 1 cylinder is at TDC-compression.
- Check valve clearance on Nos. 1, 3, and 5 exhaust and Nos. 1, 2, and 4 intake valves.
- Rotate flywheel 360° to bring No. 6 piston to TDC-compression.
- Check valve clearance on Nos. 2, 4, and 6 exhaust and Nos. 3, 5, and 6 intake valves.
- Loosen lock nut on rocker arm adjusting screw and turn screw until feeler gauge slips with slight drag.
- Hold adjusting screw and tighten lock nut to specification.
- Recheck clearance and readjust as necessary.
- Install rocker arm cover and tighten cap screws to specification.
Tools required
- JDE81-1 or JDG820 Flywheel Turning Tool Amazon
- JDE81-4 Timing Pin Amazon
- Feeler gauge Amazon
- Screwdriver Amazon
- Torque wrench Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Intake valve clearance checking: 0.41—0.51 mm (0.016—0.020 in.) cold
- Exhaust valve clearance checking: 0.66—0.76 mm (0.026—0.030 in.) cold
- Intake valve clearance adjustment: 0.46 mm (0.018 in.) cold
- Exhaust valve clearance adjustment: 0.71 mm (0.028 in.) cold
- Valve adjusting screw lock nut torque: 27 N·m (20 lb-ft)
- Rocker arm cover-to-cylinder head cap screw torque: 8 N·m (6 lb-ft) (72 lb-in.)
Source: John Deere 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.