Cylinder head (Opel Omega B)

Disassembly

1. Remove the camshaft, levers and hydraulic tappets from the cylinder head. Unscrew the glow plugs and remove the cylinder head from the engine.





2. On all models, using a valve spring compressor, compress each spring and remove the keepers from the end of the valve.





3. Remove the spring compressor and remove the spring plate and spring.





4. Using pliers, carefully remove the oil deflector cap.



5. Remove the spring seat.

6. When the valve spring is compressed and the spring cup does not come off the crackers, it is necessary to hit the spring cup with a hammer through a wooden block, which will release the crackers.

7. Remove the valve through the combustion chamber. Store each valve in a separate plastic bag along with the spring plate, spring, spring seat and crackers for later installation in their places.

Cleaning the cylinder head

1. Remove the remains of the old gasket from the cylinder head.

2. Clean carbon deposits from combustion chambers, then wash the head in a suitable solvent.

3. Clean any carbon deposits from the valves, perhaps even using a wire brush.

Examination

Cylinder head

Checking the flatness of the cylinder head



Measuring the protrusion of the swirl chamber from the cylinder head



1. Carefully inspect the cylinder head for cracks and other damage. If cracks are present, the head must be replaced.

2. Using a metal ruler and feeler gauge, check the flatness of the mating surface of the cylinder head. If the flatness is more than 0.1 mm, the head must be re-ground, while its height must meet the requirements.

3. Check the condition of the valve seats. If they are burnt, worn or defective, they must be replaced. If the valve seat is slightly worn, they must be ground in. Check the valve guides for wear by inserting the valve stem into them and moving it to the side. The movement should be insignificant. If the movement is excessive, remove the valve and measure the diameter of the valve stem. Replace the valve if necessary. If the valve stem is not worn, the guide is worn and must be replaced. Replace the valve guides at a service station.



4. If the valve seats need to be reground, this operation must be performed after installing new valve guides.

Valves

1. Check each valve head for localized corrosion, burns, cracks, and general wear. Check the valve stem for wear and bending. Check the end of the valve stem for wear. If any defects are present, the valve must be replaced.



2. Using a micrometer, measure the valve stem diameter at several points along the stem. Any significant difference in the readings indicates valve stem wear and a mandatory valve replacement.

3. If the valves are in satisfactory condition, they should be inserted into their seats and lapped. If the valve plates or seats are badly worn, they should be machined or even replaced before lapping.

Lapping valves

1. Place the cylinder head with the combustion chambers facing up on wooden blocks.



2. Lubricate the lapping paste on the valve plate and valve seat, install the valve in place and install the suction cup with the holder (handle) on the valve plate. Rotate the valve with the suction cup in different directions, lap the valve, and periodically lift the valve to redistribute the lapping paste.



3. If a coarse lapping paste is used, lap until a uniform matte surface appears on the valve seat and valve.

4. Then wipe off the used paste composition and repeat the grinding process with a fine-grained paste. Grind until a light gray-matte color appears.

5. Carefully remove traces of lapping paste using a suitable solvent.

Valve elements

1. Check the valve springs for signs of damage.

2. Install the springs with one of the ends on the frame, check the deviation of the spring axis from the vertical plane and the length of the springs. If one of the springs is damaged, all springs in the set must be replaced.

3. Replace the valve stem seals regardless of their condition.

Cylinder head assembly

1. Lubricate the valve stems with engine oil and insert them into their places. Install the valves in the places where they were ground.



(Text was copied from the portal: «OpelBook.ru»)



2. Install the spring seat.



3. Install the thin-walled protective sleeve onto the valve stem.





4. Dip the valve stem seal into fresh engine oil and install it onto the valve stem, being careful not to damage its working edges. Use a special metal mandrel to install the valve stem seals.



5. Install the valve spring and spring retainer.





6. Using a special tool, compress the valve spring and install the crackers in the recess of the valve stem and lubricate them. Remove the spring compressor. Repeat this operation on the remaining valves.

7. Using a hammer and a wooden block, tap the end of the valve stem to ensure that all valve components are firmly seated in place.

8. Install the head onto the cylinder block and install the hydraulic lifters, levers and camshaft.