Tools Required

1. Remove the upper and lower fan shroud. Refer to Engine Coolant Fan Lower Shroud Replacement and Engine Coolant Fan Upper Shroud Replacement in Engine Cooling.
2. Remove the valve rocker arm shaft, valve bridges, and pushrods for the cylinder head being service. Refer to Valve Rocker Arm, Shaft, and Push Rod Replacement .
3. Remove the glow plug for the cylinder requiring service. Refer to Glow Plug Replacement - Bank 1 or Glow Plug Replacement - Bank 2 .
4. Remove the fuel injector return pipe bolts and washers.
5. Remove the fuel injector return pipe.



6. In order to apply shop air to the cylinders use the following procedures to modify J 26999-20  (1) and J 26999  (2):

6.1.	Remove the valve core from J 26999-20 to allow air to flow.

6.2.	Remove the quick connect fitting from J 26999 .

6.3.	Adapt the quick connect fitting in order to use for shop air.

6.4.	Connect the quick connect fitting to J 26999-20 .

Important: Rotate the cylinder to be serviced to the bottom of the stroke. This is to ensure that the engine does not rotate when the compressed air is applied to the cylinder being serviced.

7. Install J 26999-20 into the glow plug hole for the cylinder being serviced.
8. Apply compressed air to hold the valves in place. If the compressed air is released, the valves can drop into the cylinder.




Caution: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

9. Install J 44646 to the rocker arm bosses on the cylinder head.

J 44646 should be installed in the rocker arm boss next to the cylinder being serviced. The pivot pin can be removed from the stand to allow the stand to be installed. The lever has different locating holes for the pivot pin depending on available clearance. The lever is also notched for different locations of the compressor.

10. Using J 44646 compress the valve spring.
11. Remove the valve keys from the valve stem.
12. Carefully release the valve spring tension.



13. Remove the valve spring upper seat (2) and the valve spring (3).
14. Remove the valve stem oil seal (4).
15. Remove the valve spring lower seat (5).
16. Continue removing the remaining valve stem seals for the cylinder using the above procedure.

Notice: Air pressure should remain applied to the cylinder for installation.

1. Install the valve spring lower seat.
2. Install the valve stem seal using J 44640 .



3. Install the valve spring (3), the painted end of the valve spring goes toward the cylinder head.
4. Install the valve spring upper seat (2).




Caution: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

5. Using J 44646 compress the valve spring.
6. Install the valve keys to the valve stem.

Notice: The valve stem keys must correctly seat in the valve spring cap. Engine damage may occur by not installing properly.

7. Carefully release the valve spring pressure. Make sure the valve keys stay in place.
8. Continue to install the 3 remaining valve stem seals for the cylinder.



9. Release the compressed air holding the valves in place.
10. Remove J 26999-20  (1) from the glow plug hole.
11. Continue to replace the valve stem seals on the remaining cylinders using the above procedures.



12. Install the fuel injector return pipe.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

13. Install the fuel injector return pipe to injector bolts and washers.

Tighten
Tighten the bolts to 16 N·m (12 lb ft).

14. Install the fuel injector return pipe to cylinder head bolts and washers.

Tighten
Tighten the bolts to 17 N·m (13 lb ft).




15. Install the glow plug to the cylinder being serviced.

Tighten
Tighten the plugs to 18 N·m (13 lb ft).

16. Install the glow plug. Refer to Glow Plug Replacement - Bank 1 or Glow Plug Replacement - Bank 2 .
17. Install the valve rocker arm shaft, the valve bridges, and the push rods. Refer to Valve Rocker Arm, Shaft, and Push Rod Replacement .
18. Install the upper and lower fan shroud. Refer to Engine Coolant Fan Lower Shroud Replacement and Engine Coolant Fan Upper Shroud Replacement in Engine Cooling.