printable version
Dismantling, check and assemblage of the cylinder head
Dismantling
| Fig. 2.123. Procedure for loosening bolts of the cylinder head
|
With a special tool (key 09221-32001), unscrew the cylinder head bolts in the order shown in Figure 2.123.
With a special tool (fixture to compress the valve springs 09222-28000 and 09222-28100 adapter) compress the spring and remove crackers. Remove the valve spring retainer, valve spring, spring seat valve and the valve (Fig. 2.124).
NOTE Keep parts for each valve separately set so as not to confuse them when installing. |
With a special tool (extractor valve stem seals 09222-29000), remove the valve stem seals (Fig. 2.125).
NOTE Re-installing the valve stem seals is not allowed. |
Check the cylinder head Inspect the cylinder head for cracks, damage and leakage of coolant. If cracks are found, replace the cylinder head.
| Fig. 2.126. Cleaning the surface of the cylinder head
|
Thoroughly clean the cylinder head from the scale, sludge and remnants of the old sealant and gaskets. Clean oil passage, blow with compressed air (Fig. 2.126).
| Fig. 2.127. Driving test the flatness of the mating surface of the cylinder head
|
Check the flatness of the cylinder head mating surfaces in the directions shown in the figure. If the flatness exceeds the limit in any direction, either replace the cylinder head or pereshlifuyte mounting surface of the cylinder head (Fig. 2.127). Values flatness mating surface of the cylinder head are shown below. Nominal value: less than 0.03 mm. Limit: 0.2 mm.
Check valves
Check each valve for wear, damage and deformation of the plate and the zone ?�B?� of the valve stem. Replace the valve if necessary. If at the end of ?�A?� valve stem formed dents or present considerable wear, if necessary, treat the end of the valve stem. The thickness of the release layer in the machining end of the valve stem must be minimal. In addition, process working facet of the valve seat (Fig. 2.129). Replace the valve if its thickness plates less than the limit. The nominal value of the thickness of the valve disc: inlet valve - 1.0 mm; exhaust valve - 1.5 mm. Limit: inlet valve - 0.7 mm; exhaust valve - 1.0 mm.
Checking valve springs
Check the length of the valve spring in the free state. If the length of the spring is less than the limit, replace the valve spring (Fig. 2.130). With check-square deviation from the spring axis perpendicular to the supporting surface (perpendicularity). If perpendicularity over the limit, replace the valve spring. Nominal dimension values given below of the valve spring. The length of the spring in a free state: 45.82 mm. Spring length under a load of 25.3 kg: 40,00 mm. Deviation spring axis (perpendicularity): 1.5 ?� or less. Limit values measurement valve springs are shown below. The length of the spring in a free state: 44.82 mm. The deviation of the spring axis (perpendicularity) 4 ?�.
Checking the valve guides
Check the clearance between the guide and the valve stem (several points along the length). If the clearance is more than the limit, replace the valve guide (Fig. 2.131). The clearance between the guide and the valve stem are shown below. Nominal value: inlet valve - 0,020-0,047 mm; exhaust valve - 0,050-0,085 mm. Limit: inlet valve - 0.10 mm; exhaust valve - 0.15 mm.
Restoration of the valve seat
Check the valve seat for signs of overheating and uneven contact with the shut-off valve disc facet. If necessary, repair or replace the valve seat. Before restoring the valve seat check valve guide for wear. If the guide sleeve is worn, replace it first, and then restore the valve seat. Restoration of the valve seat is made special tool (cutters or machine tools). The width of the stop valve seat chamfer must correspond to the nominal values and the contact patch must be placed evenly in the middle of a working facet of the valve disc. After the restoration of the valve seat and the seat should be lapped using lapping compound (Fig. 2.132).
Replacing the valve seat
| Fig. 2.133. The residual amount of metal in the processing replaceable valve seat
|
Cut a replaceable valve seat, a residual amount of metal shown in figure 2.133. Chisel a hole in the cylinder head for the installation of the valve seat corresponding repair size (larger diameter). Heat the cylinder head to a temperature of about 250 ?� C and press-fit oversize seat in the cylinder head. Grind to a new valve seat using lapping compound. The width of the locking facet of a saddle valve: 0.9-1.3 mm.
Replacing the valve guide
With a special tool (Tool for fitting the guide sleeve 09221-22000A), press out the old valve guide from the cylinder head in the direction of the surface of the gasket (Fig. 2.134). Ream hole for installation of the cylinder head valve guide corresponding repair size (larger diameter).
| Fig. 2.135. The difference in the length of the guides for the intake and exhaust valves
|
With a special tool (Tool for fitting the guide sleeve 09221-22000V) press in the new valve guide from the bed of a camshaft. Note the difference in the length guides for the intake and exhaust valves (Fig. 2.135). After installing the valve guide, insert a new valve and check that the gap between the guide sleeve and the shaft of the valve corresponds to the nominal value. After replacing the valve guide, check for correct seating in the valve seat. If necessary, treat the valve seat.
Assembly Install the valve spring seat.
NOTE Clean all parts before assembly. Apply engine oil to all rubbing and rotating parts. |
With a special tool (mandrel to install the valve stem seal 09222-22001) a light blow install the valve stem seal in place (Fig. 2.136).
NOTE The reuse valve stem seals is not allowed. Improper installation of the valve stem seal can lead to oil leakage through the valve guide. |
Lubricate the valve stem with engine oil. Insert the valve into the valve guide. Do not force the passage of the valve stem through the valve stem seal. After installing the valve, check the smoothness of its movement.
| Fig. 2.137. The scheme of installation of the valve spring
|
Install the valve spring so that the painted coil spring was located near the spring plate (top), and then install the valve spring plate (Fig. 2.137). With a special tool (fixture to compress the valve springs 09222-28000 and 09222-28100 adapter) compress valve spring and establish crackers. Before removing the special tool after installing the valve check the reliability of the installation of crackers.
NOTE When compressing the valve spring, take care to not touch the plate spring valve stem seal. |
Clean the gasket plane of the gasket on the cylinder head and cylinder block. Check the identification marks cylinder head gasket technical data. Install the cylinder head gasket on the engine block with an identification mark up (to the cylinder head). Before installing the cylinder head bolts, measure their length. The maximum length of the bolt: 99.4 mm.
| Fig. 2.138. Order of a tightening of bolts of the cylinder head
|
Tighten the cylinder head bolts to the specified torque in the order shown in Figure 2.138. Tightening torque of the replacement parts head unit or head bolts): 63 N ?� m + release all screws by 20 Nm to + 90 ?� to + 90 ?� without replacing parts: 20 Nm + 90 ?� + 90 ?�.
|