Mitsubishi 4M50 Valve Adjusting Procedure, Valve Lash Clearance, Valve Train Parts Page,

MITSUBISHI 4M50 Valve Adjusting Procedure, Valve Train Parts, Page 1 of 5

Inspection and Adjustment of Valve Clearances Service standards (Unit: mm {in.}) Location –

Maintenance item Mitsubishi 4M50 Valve Lash Clearance (when cold)

Standard value

Limit

Intake valve

0.4 MM {0.016 Inch}

–

Exhaust valve

0.5 MM {0.020 Inch}

–

Remedy Adjust

Mitsubishi 4M50 Tightening torque (Unit: N·m {lbf·ft, kgf·m}) Mark

Parts to be tightened

Tightening torque

Remarks

23.2 {17, 2.4}

–

30.4 to 35 {22 to 26, 3.1 to 3.6}

–

Bolt (cover installation) Bolt (rocker cover installation) Bolt (PCV pipe installation) Injection pipe (union nut installation) Bolt (injector installation) –

5.2 to 7.2 {3.8 to 5.3, 0.53 to 0.73}

–

Bolt (cylinder sensor installation)

8 {5.9, 0.82}

–

Lock nut (adjusting screw stopping)

20.6 {15, 2.1}

–

Special tools Mark

Tool name and shape

Part No.

Application

Cranking handle (design may vary)

MH063704

Turning the fan pulley

Fuel line wrench

HAZET 4550-1 SnapOn FRXM17

Tightening the fuel lines

Mitsubishi 4M50 Engine Parts contact: Email: EngineParts@HeavyEquipmentRestorationParts.com Phone: 269 673 1638

MITSUBISHI 4M50 Valve Adjusting Procedure, Valve Train Parts, Page 2 of 5

Rocker Cover Rubber

Injector Fuel Return Line

Injector Bolts 4M50 Injector Wire Harness

4M50 Injector Injector Line Injector Oring

Cylinder Sensor

Injector Sealing Washer Rocker Cover Bolts

Rocker Cover

Rocker Cover Gasket A Rocker Cover Gasket B

MITSUBISHI 4M50 Valve Adjusting Procedure, Valve Train Parts, Page 3 of 5 1 2 3 4 5 6

1 2 3 4 5

Oil filler cap Cover Rocker cover rubber Snap ring Fuel return hose Fuel line

Air inlet duct Gasket Intake throttle Gasket 4M50 Intake manifold

7 8 9 10 11 12

13 Rocker cover 14 4M50 Rocker cover gasket A 15 4M50 Rocker cover gasket B

Bolt (with hexagonal hole) 4M50 Injector 4M50 Injector O-ring 4M50 Injector Tip gasket PCV pipe Cylinder sensor

: Non-reusable parts PCV: Positive Crankcase Ventilation

Adjust the valves when the engine is cold.

1. Blank 2. Disconnect the EGR harness at the throttle body.

3. Remove the air inlet duct mounting bolts and remove the intake throttle.

4. Remove the oil cap.

5. Remove the cover.

6. Remove the rocker cover rubber.

7. Using compressed air, blow any debris from around the injectors.

8. Disconnect the fuel return lines.

9. Disconnect the wire harness from the injectors.

10. Remove the fuel return line mount bolts (one on the valve cover and one on the side of the engine). Carefully move the return line out of the way.

11. Remove the fuel lines.

12. Remove the injectors.

13. Disconnect the PCV pipe at the left of the engine and move it out of the way.

14. Remove the cylinder sensor.

15. Remove the rocker cover.

16. Rotate the engine until the number one cylinder is at TDC. The timing mark on the left camshaft will line up.

Verify that the flywheel is also show-ing the “I, IV” mark.

NOTE: Mark the flywheel for easy access later.

Cylinder No.

1

2

3

4

Valve

IN

EX

IN

EX

IN

EX

IN

EX

No. 1 cylinder piston at TDC on compression stroke

O

O

O

–

–

O

–

–

No. 4 cylinder piston at TDC on compression stroke

–

–

–

O

O

–

O

O

Mitsubishi 4M50 Engine Parts contact: Email: EngineParts@HeavyEquipmentRestorationParts.com Phone: 269 673 1638

MITSUBISHI 4M50 Valve Adjusting Procedure, Valve Train Parts, Page 4 of 5 17. Adjust the valve clearances.

• Loosen the lock nut.

• Back off the adjuster screw and insert the feeler gauge under the rocker.

• Tighten the adjuster screw until the feeler gauge drags slightly.

• Hold the adjuster screw in position and tighten the lock nut. See tightening table.

• Recheck the valve clearance with the thickness gauge, and readjust if the measurements are not within the specified value range.

• Repeat for each valve.

• Rotate the engine one turn to the #4 position, and adjust remaining valves.

18. Make sure that all 4M50 gaskets are securely in place and install the rocker cover.

19. Install the 4M50 injectors.

20. Connect the 4M50 fuel return lines.

21. Install the 4M50 fuel return line mount bolts.

22. Install the 4M50 fuel lines.

23. Position and connect the PCV pipe.

24. Install the rubber.

25. Install the cover.

26. Install the throttle body and air inlet duct.

27. Connect the EGR harness at the throttle body.

28. Start the engine and verify proper operation.

Mitsubishi 4M50 Engine Parts contact: Email: EngineParts@HeavyEquipmentRestorationParts.com Phone: 269 673 1638

MITSUBISHI 4M50 Valve Adjusting Procedure, Valve Train Parts, Page 5 of 5 Mitsubishi 4M50 Valve Train Parts Mitsubishi 4M50 Cylinder Head Parts Exhaust Rocker Arms Exhaust Rocker Arm Bushings Exhaust Rocker Arm Adjusting Screws Lock Nuts

Exhaust Rocker Shaft 4M50 Exhaust Manifold Side Exhaust Gaskets, Exhaust Studs, Bolts, Nuts,

Intake Rocker Arms 4M50 Intake Manifold Side Intake Gaskets, Intake Studs, Bolts, Nuts,

Intake Rocker Arm Bushings Intake Rocker Arm Adjusting Screws Locks Nuts

Intake Rocker Shaft Exhaust Rocker Shaft Valve Cotters

Upper Valve Spring Retainer Intake Rocker Shaft Intake Camshaft

Exhaust Camshaft

Outer Valve Spring

Valve Stem Seal

Inner Valve Spring

4M50 Exhaust Valve Guide Exhaust Valve Seat Exhaust Valve

Intake Valve

4M50 Intake Valve Guide Intake Valve Seat

Rocker Shaft Spring

Head Bolts Intake Valves

• Mitsubishi 4M50 Engine Parts contact: Email: EngineParts@HeavyEquipmentRestorationParts.com

Exhaust Valves

Phone: 269 673 1638