Contents: Disassembly 🠛 Assembly 🠛
Fig. 2.28. Using the valve spring compressor
Fig. 2.29. Using a special device to install the oil deflector cap
Fig. 2.30. Details of the valve installed in the cylinder head: 1 - spring seat; 2 - oil deflector cap; 3 - spring; 4 - upper spring plate; 5 - crackers
Disassembly
- Remove the camshaft thrust bearing mounting bolt.
- Loosen the bolt, remove the longitudinal movement lock and release the camshaft.
- Using a valve spring compressor, compress the first valve spring and remove the keepers.
- Gently loosen the spring compressor and remove it.
- Remove the spring plate, spring and spring seat and arrange the parts in the order they were removed.
- Remove the springs from the remaining valves in the same manner.
- Remove the oil seals and valves.
- Check the valve guides for wear. Insert the valve into the guide. The valve should move easily in the guide, without any lateral play. Special tools are required to replace worn guides with new ones.
- Check the valve heads and valve seats for chipping and burning. Light chipping on the valve and seat can be removed by lapping, first with coarse and then with fine grinding paste.
- If there are deep traces of chipping, the valves must be ground on a valve grinding machine, and the seats - on a valve seat milling machine. For the last two types of work, you must contact specialists.
- After any treatment, clean the cylinder head.
- Neutralization of sodium contained in exhaust valves
- Before disposing of the exhaust valves, the sodium contained in them must be neutralized.
- Valves should be sawed in a dry room without any contact with water (do not use wet abrasive sharpening tools).
- Wear safety glasses.
- Saw the valve stems where they expand.
- Prepare a container filled with water and place it outside (approximately 10 liters of water for four valves).
- Immediately after sawing, immerse the sawn valves in water, avoiding splashing.
- Sodium reacts with water to form caustic soda with the release of hydrogen. The complete destruction of sodium is indicated by the cessation of hydrogen release (in the form of bubbles).
- Keep the container away from fire until the reaction is complete (no smoking).
- Valves treated in this way can be thrown away. Before removing them from the container, put on waterproof gloves.
- Rinse the container with plenty of water.
- If the solution comes into contact with your skin or eyes, rinse immediately with plenty of water and consult a doctor
Assembly
- Lubricate the first valve stem with engine oil and insert it into the guide. Install the valve stem seal.
- Install the spring seat, spring and spring plate
- Compress the valve spring with a spring compressor and insert the crackers into the top of the valve stem
- Slowly remove the spring compressor and check that the crackers are in place.
- Install the remaining valves into the cylinder head in the same manner.
- Once all the valves are in place, lightly tap the top of the valve springs with a plastic hammer to ensure the keepers are seated.
- Install the camshaft and camshaft retainer, but do not tighten the camshaft retaining bolt