Removing
When removing the chain, the operations are performed in the following order:
- drain the coolant from the engine cooling system;
- remove the air filter and battery;
- disconnect the choke drive cable from the carburetor, and the carburetor throttle drive rods from the lever on the cylinder head cover;
- remove the cylinder head cover, radiator with casing, disconnecting hoses and wires;
- loosen the tension and remove the alternator drive belt.
- turn on the 4th gear in the gearbox, unscrew the bolt and remove the generator drive pulley from the crankshaft;
- unscrew the bolts securing the camshaft drive cover to the oil sump and cylinder block and remove the cover;
- screw the bolt into the front end of the crankshaft;
- set the gearshift lever to neutral position and turn the crankshaft until the alignment mark on the crankshaft sprocket aligns with the mark on the cylinder block (pic. 24), and the marks on the camshaft sprocket with the mark on the bearing housing (see fig. eleven);
- loosen the cap nut of the chain tensioner, press the tensioner rod with a mounting spatula and fix it with the cap nut. Remove the sprockets from the camshaft and from the accessory drive shaft. Unscrew the limit pin 6 (see fig. 20) chains and remove the chain.
Installation
Lubricate the chain with engine oil before installation, and then perform the operations in the following order.
- Install and secure the chain sprocket to the accessory drive shaft.
- Put the chain on the crankshaft sprocket and wrap the chain stop pin.
- Install the camshaft sprocket by putting a chain on it and aligning the marks (see fig. eleven), and do not completely tighten the sprocket mounting bolt.
- Loosen the chain tensioner cap nut, rotate the crankshaft two turns and tighten the nut. Check label match (see rice. eleven and 24). If the marks do not match, then reinstall the chain, and if they match, then finally tighten the bolts securing the camshaft sprockets and the auxiliary drive shaft.
- Install all removed components and parts on the engine and vehicle.
After replacing the chain, check and adjust the ignition timing, the tension of the alternator drive belt, as well as the carburetor air and throttle actuators (see section «Engine settings»).