Mitsubishi 6M60 Engine Valve Adjustment Procedure, Valve Lash Clearance, Cylinder Head Parts, Valve Train Parts, Page 1 of 6
Mitsubishi 6M60 Inspection and Adjustment of Valve Clearances Service standards (Unit: mm) Location –
Maintenance item
Standard value
Mitsubishi 6M60 Valve clearance (when cold)
Limit
Remedy
–
Adjust
0.6 MM or .024 Inch
Tightening torque (Unit: N·m {kgf·m}) Mark
Parts to be tightened
Tightening torque
Remarks
–
Lock nut (adjusting screw tightening)
59 Nm {6.0 kgfm} 43 Ft Lbs
–
–
Lock nut (rocker arm adjusting screw tightening)
34 Nm {3.5 kgfm} 25 Ft Lbs
–
Special tools Mark
Tool name and shape
Socket wrench
Part No.
MH063003
Application
Tightening the lock nut
• Valve clearances should be checked and adjusted as follows
Mitsubishi 6M60 Engine Parts while the engine is still cold. contact email: EngineParts@HeavyEquipmentRestorationParts.com Contact phone: 269 673 1638
Mitsubishi 6M60 Engine Valve Adjustment Procedure, Valve Lash Clearance, Cylinder Head Parts, Valve Train Parts, Page 2 of 6 • Remove the rocker cover. • Bring the No. 1 or No. 6 cylinder piston to the top dead center (TDC) on the compression stroke according to the following procedure: • Rotate the crankshaft until the pointer is aligned with the “1 6” mark on the flywheel. • This will place either the No. 1 or No. 6 cylinder piston at TDC on the compression stroke. The cylinder in which the rocker arms for both the intake and exhaust valves can be pushed down by hand by the valve clearance amounts has its piston at TDC. Rotate the engine by one full turn to switch the TDCs of the No. 1 and No. 6 cylinder pistons. • With the No. 1 or No. 6 cylinder piston at TDC, measure the clearance of the valves (clearance between valve bridge and pad) marked with a circle in the table below. Cylinder No. Valve
1
2
3
4
5
6
IN EX IN EX IN EX IN EX IN EX IN EX
No. 1 cylinder piston at TDC on O compression stroke
O
O
–
–
O
O
–
–
O
–
–
No. 6 cylinder piston at TDC on compression stroke
–
–
O
O
–
–
O
O
–
O
O
–
• Any attempt to insert a feeler gauge without first securing sufficient space, as described above, between the pad and the valve bridge will fail, as the pad will tilt as shown in the illustration, thus blocking the entry of a feeler gauge.
• Before inserting a feeler gauge, push the adjusting screw pad on the side opposite from where a feeler gauge is to be inserted, as shown in the illustration, using a flat-head screwdriver or other similar tool. This will create space necessary for the gauge to be inserted. • The measurement is correct when the feeler gauge feels slightly resisted as it is inserted. • The measurement is not yet correct if the feeler gauge can still be inserted smoothly. • If the measurement deviates from the standard value, adjust as follows.
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Mitsubishi 6M60 Engine Valve Adjustment Procedure, Valve Lash Clearance, Cylinder Head Parts, Valve Train Parts, Page 3 of 6 [Mitsubishi 6M60 Valve Adjustment] • Loosen the lock nuts and adjusting screws on the valve bridge and rocker arm.
• While holding the valve bridge by hand, screw in the adjusting screw until it lightly contacts the valve stem end. • Then, further screw in the adjusting screw by 45°.
• While holding the adjusting screw in this position with a socket wrench and extension, tighten the lock nut to the specified torque using .
CAUTION • After adjusting the adjusting screw, be sure to tighten the lock nut to the specified torque. Insufficient torquing will compromise the parallelism of the valve bridge, damaging the valve mechanism.
Tightening torque (Unit: N·m {kgf·m}) Mark
Parts to be tightened
Tightening torque
Remarks
–
Lock nut (adjusting screw tightening)
59 Nm {6.0 kgfm} 43 Ft Lbs
–
–
Lock nut (rocker arm adjusting screw tightening)
34 Nm {3.5 kgfm} 25 Ft Lbs
–
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Mitsubishi 6M60 Engine Valve Adjustment Procedure, Valve Lash Clearance, Cylinder Head Parts, Valve Train Parts, Page 4 of 6 • Screw in or out the adjusting screw on the rocker arm until the correct feeler gauge can be inserted with a slight resistance. • While holding the adjusting screw in this position with a screwdriver, tighten the lock nut to the specified torque using . • Recheck the valve clearance using the correct feeler gauge.
[Installation] • Before installing the rocker cover, reapply sealant to the packing (half-round) between the rocker case upper and rocker case. • Rocker Cover, Valve Cover bolts tightening torque 7 Ft Lbs
Mitsubishi 6M60 Engine Parts: www.6M60.com Contact email: EngineParts@HeavyEquipmentRestorationParts.com Contact phone: 269 673 1638
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Mitsubishi 6M60 Engine Valve Adjustment Procedure, Valve Lash Clearance, Cylinder Head Parts, Valve Train Parts, Page 5 of 6
1. Mitsubishi 6M60 Engine Valve Train
• The 6M6 engine employs an overhead camshaft (OHC) system, with the valve mechanism and the timing gears arranged as shown above.
Mitsubishi 6M60 Engine Valve Adjustment Procedure, Valve Lash Clearance, Cylinder Head Parts, Valve Train Parts, Page 6 of 6
2. Mitsubishi 6M60 Rocker and Bracket Assembly, Camshaft, Rocker Case and Cylinder Head Gasket • The camshaft is directly supported at its journals by the rocker case, and is held in place from above by the rocker and bracket assembly. • The camshaft journals are directly supported by the rocker case and the rocker and bracket assembly, without using any camshaft bearings. The rocker case and brackets have been machined together, meaning that they all need to be replaced for a new set when one of them becomes defective.
Mitsubishi 6M60 Engine Parts: www.6M60.com Contact email: EngineParts@HeavyEquipmentRestorationParts.com Contact phone: 269 673 1638
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