Note. The design of the cylinder head does not allow the removal of pushers until the head itself and its gasket are removed. In view of the foregoing, the procedure for removing pushers is considered separately in the Section on maintenance of the camshaft and pushers.
Removal and disassembly
1. Disconnect the negative cable from the battery.
2. Remove the air cleaner assembly.
Note. To prevent debris and foreign objects from entering the carburetor, cover its neck with a rag.
4. Mark and disconnect all hoses and cables interfering with removal of a cover of a head of cylinders.
5. Gradually, a quarter of a turn at a time, loosen the cover bolts - start with the outer bolts and work your way inward. Remove the cylinder head cover, taking care to keep dirt and debris out of the engine.
6. Use a screwdriver or wrench to loosen all valve clearance screws until the valves are completely unloaded.
7. Gradually, moving from outside to inside, loosen the bolts of the pedestals of the axis of the rocker arms.
8. Rotate the pusher rods to release them from the rocker arms and carefully remove the rocker assembly.
9. Remove the pusher rods, folding them in accordance with their placement on the engine - it is best to make a special template rail made of thick cardboard for orderly storage of the pusher rods.
10. Remove the components from the rocker shaft by stacking them in the order in which they were placed on the assembly.
Cleaning and checking the condition
1. Wash all removed components in a suitable solvent, then dry thoroughly with compressed air.
2. Check the patency of all oil flows of the assembly components, blow out the channels and holes with compressed air.
3. Check all components for signs of wear and mechanical damage. Replace defective parts.
4. Check up a condition of working surfaces of yokes contacting to cores of valves. If there are signs of excessive wear, replace the defective rocker arm. Light mechanical damage in the form of scratches can be repaired with an oil dressing whetstone.
5. Using a suitable micrometer, measure the inner diameters of the axial holes of the rocker arms and the diameters of the axis of the rocker arms in the areas where the latter are located. By subtracting the second results from the first results, determine the landing clearances of the rocker arms. If the gaps exceed the allowable values (see tables of sizes and adjustments at the end of the guide) replace worn components.
Assembly and installation
Assembly and installation are carried out in the reverse order.
1. Before starting assembly, generously lubricate the working surfaces of the rocker arms and their axles with impellent oil.
2. Put the assembly components on the axis of the rocker arms in the same order (valve drive components are shown in the accompanying illustration).
1 - assembly of the axis of the rocker arms; 2 - bolts; 3 - washers; 4 - rocker arms; 5 - pedestals; 6 - spring
3. Lubricate the ends of the push rods with engine oil and insert the rods into their sockets in the cylinder head.
4. Install the rocker arm assembly into the cylinder head (see accompanying illustration) and hand-tighten the mounting bolts. Make sure that the spherical tips of the screws of all the rocker arms correctly fall into the nests of the saddles of their pushers.
5. Tighten the pedestal mounting bolts to the correct torque in several stages.
6. On a cold engine, install the valve clearances. Temporarily install the cylinder head cover and air cleaner, and after starting the engine, warm it up to normal operating temperature. Check the valve clearance setting on a warm engine, adjust if necessary.
7. Remove the cylinder head cover and reinstall with a new gasket, engine oil filler neck forward. Screw in the mounting bolts and tighten them in two stages, moving in a spiral from the inside out.
8. Reattach all hoses and cables removed during removal.
9. Replace the air cleaner assembly.
10. Start the engine and check for signs of oil leaks.