Valve Spring: Service and Repair

Valve Stem Oil Seal and Valve Spring Replacement

^ Tools Required
- J 26999 Compression Gage
- J 26999-10 Compression Gage Adapter
- J 26999-30 Compression Gage Adapter
- J 38606 Valve Spring Compressor

Removal Procedure





1. Remove the engine cover from the vehicle.
2. Disconnect the battery negative cables from the batteries.

Notice: All valve train components must be reassembled in the exact order and position from which they were removed.

3. Remove the valve rocker arm, shaft, and the push rod from the cylinder being serviced.
4. Remove the glow plugs from the cylinder being serviced.
5. Modify the J26999-10 and the J26999-30. A valve core is used to prevent the lost of engine compression when using for compression test.
5.1. Remove the valve core from the J26999-10 or the J 26999-30.
5.2. Remove the quick connect fitting from the J 26999.
5.3. Adapt the quick connect fitting in order to use for shop air.

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.

6. Install the J 26999-10 (2) or the J 26999-30 into the glow plug hole.
7. 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.

Notice: Completely engage the J 38606 jaws on the valve spring. The J 38606 may slip off and scratch the valve spring. Replace the valve spring if the valve spring becomes scratch.

8. Use the J 38606 (1) in order to compress the valve spring. If the spring will not compress, tap on the tool lightly with a mallet in order to loosen the cap or rotator from the valve keys.





9. Remove the valve keys from the valve stem (exhaust valve shown).
10. Carefully release the valve spring tension.
11. Remove the cap or the rotator, the shield, and the valve spring with the damper (exhaust valve shown).
12. Remove the valve stem oil seals.

Installation Procedure

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





1. Apply a small amount of clean engine oil to the valve stem.
2. Install the new valve stem oil seals.
3. Install the valve spring with the damper, the shield, and the cap or the rotator (exhaust valve shown).





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.

Notice: Completely engage the J 3606 jaws on the valve spring. The J 38606 may slip off and scratch the valve spring. Replace the valve spring if the valve spring becomes scratch.

4. Install the valve keys. Use grease in order to hold the valve keys in place.

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

5. Carefully release the valve spring pressure. Make sure the valve keys stay in place.
6. Remove the J38606 (1).
7. Remove the J26999-30 (2) or the J26999-10.
8. Install the glow plugs to the cylinder being serviced.
9. Install the valve rocker arm, shafts, and the push rod to the cylinder being serviced.
10. Install the engine cover to the vehicle.
11. Connect the battery negatives cables to the batteries.