Doosan — Check and Adjust Engine Valve Clearance
Adjustments · Engine valve train
From a Doosan owner's manual covering: G 100, G100-SIIIA, G100SIIIA, G150, G150-SIIIA, G200-SIIIA, G60, G60-SIIIA, G60SIIIA, G80, G80-SIIIA, G80SIIIA. Check it applies to your exact model before use.
Applies to: Doosan G100-SIIIA, Doosan G150-SIIIA, Doosan G200-SIIIA, Doosan G60-SIIIA, Doosan G80-SIIIA, John Deere 4045HFG81 engine, John Deere 4045HFG82 engine, John Deere 6068HFG82 engine
Procedure
- Remove rocker arm cover and crankcase vent tube.
- Rotate flywheel until No. 1 piston is at TDC compression stroke; insert timing pin.
- Check and adjust valve clearance to specification.
- Loosen locknut on rocker arm adjusting screw; turn screw until feeler gauge slips with slight drag.
- Hold adjusting screw and tighten locknut to 27 N·m (20 lb.-ft.).
- Recheck clearance after tightening locknut.
- Rotate flywheel 360 degrees and adjust remaining valves per firing order.
- Reinstall rocker arm cover and crankcase vent tube.
Tools required
- JDE83 or JDG820 Flywheel Turning Tool Amazon
- Timing pin JDG1571 Amazon
- Feeler gauge Amazon
- Screwdriver and wrench Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Intake 0.35 mm (0.014 in.) cold
- Exhaust 0.45 mm (0.018 in.) cold
- 4045 firing order 1-3-4-2
- 6068 firing order 1-5-3-6-2-4
Full service-parts list: Doosan G100-SIIIA →, Doosan G150-SIIIA →, Doosan G200-SIIIA →, Doosan G60-SIIIA →, Doosan G80-SIIIA →, John Deere 4045HFG81 engine →, John Deere 6068HFG82 engine →
Source: Doosan owner's 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.