Note 1: Broken springs and valve stem seals can be replaced without removing the cylinder head from the engine. This operation will require a few special tools, as well as a source of compressed air, so read the entire paragraph to assess your ability to cope with this job.
Note 2. On engines manufactured since 1998, before starting the operation, check the clearances in the valves (see chapter 1), since clearance adjustment can be combined with this procedure.
1. Remove the distribution lead (see paragraph 7). Remove the pushers from the drive of the faulty valves. Store the tappets in the order in which they were installed on the engine. When assembling, they should hush up their previous position.
2. Turn out a candle from the cylinder with the faulty valve. If you plan to replace all valve caps, remove all spark plugs.
3. Rotate the crankshaft until the respective piston is at TDC on the compression stroke (see paragraph 3). If all valve caps are to be replaced, start with cylinder #1 and move on to the next cylinders in turn according to the firing order of the cylinders (see technical data at the beginning of this chapter).
4. Screw a long adapter into the spark plug hole, to the second end of which connect a hose from a compressed air source (pic. 5.4) (the compressed air in the cylinder will hold the valves up until the spring is removed from them).
5. Apply compressed air to the cylinder. Be careful: under the action of compressed air, the piston can go down and suddenly turn the crankshaft. If the wrench that you used to turn the crankshaft is still on the crankshaft shank bolt, it may cause injury or significant damage to the vehicle when turning the crankshaft.
6. The valves should now be held closed with compressed air.
7. Plug all the holes in the cylinder head around the valves with clean rags so that no foreign object falls into the cylinder. Using the tool, compress the valve spring and remove the crackers from the upper spring plate (pic. 5.7).
Note. To compress the springs, you will need a special tool that can be fixed in the right place without removing the cylinder head.
8. Remove the top plate, spring and spring washer. Note the depth of the cap in the head and pull the cap out (pic. 5.8). Mark the parts or store them so that the set of parts will be in the same place during assembly.
Note. If compressed air does not hold the valve closed during this operation, the valve itself or its seat may be damaged. In this case, the cylinder head will have to be removed.
9. Inspect the valve spring for cracks or other damage. Measure the free length of the spring and compare it with the value given in Technical data chapter 2B.
10. Lubricate the valve stem with engine oil and insert a new oil cutter cap into its socket. Push the cap to its original depth using a special adapter or a long socket wrench (pic. 5.10).
11. Insert support washer and spring (pic. 5.12). Install the spring with close coils towards the cylinder head.
12. Install the top valve disc. Compress the spring and carefully insert the cotters into the groove of the valve stem. Apply some grease to the nuts to keep them from falling out during installation (pic. 5.12).
13. Slowly release the spring compressor making sure the nut is securely in place.
14. Turn off the compressed air, disconnect the hose and unscrew the adapter from the spark plug hole,
15. Insert the pushers and install the camshaft (see paragraph 7).
16. Establish the remained details in sequence, return to their removal.
17. Start the engine, check for leaks and unusual valve noises.
Note. On pre-1998 exit models, the hydraulic tappets may be noisy at first. This noise should gradually disappear as the tappets fill with oil.