Vaz 21213, Руководство по ремонту, Страница: 32 / 222

For lever springs (Fig.2-53) the size Ä (spring unloaded)
must be 35 mm, whereas the size Ç (spring loaded 51-73.5 N/
5.2-7.5 kgf) must be 43 mm.
Cylinder head bolts. Multiple use of the cylinder head bolts
results in the bolt elongation. Therefore, check the length of the
bolt (L) to be 120 mm (less the bolt head length), otherwise
renew the bolt.
When replacing the bolts take care not to fit similar bolts from
other VAZ engines of the same type (2101, 21011, 2103, 2107,
2121), but made of different steel.
The 21213 engine bolts have the threaded area of 70 ÏÏ (30
mm for other engines); in addition, the 21213 engine bolts do not
have a distinctive mark (a 7.5 mm diameter recess for wrench).
Valve rocker levers.
Check the condition of the lever oper-
ating surfaces which mate the valve stem, cam lobe and adjuster
bolt spherical end.
Always renew the rocker arm when its surfaces are chipped,
scored or scuffed.
Renew the lever adjuster bolt bush or the bolt itself in case of
any deformation or damages found.
Camshaft and timing gear
Design description
Camshaft is cast iron, of five bearings, operates in the alu-
minium bearing housing fitted to the cylinder head.
Basic dimensions of the camshaft and bearing housing are
shown in Fig.2-54. The flanks of the cams are chilled for better
wear resistance.
In order to eliminate the camshaft endfloat, the camshaft is
supported by the thrust flange held in the front journal groove.
Camshaft is operated through crankshaft sprocket 5 (Fig. 2-
55) and double-row roller chain 2. The chain also operates
sprocket 4 of the oil pump shaft. The chain drive has semi-auto-
matic tensioner 8 with shoe 7 and chain damper 3 with rubber
covers.
In the cylinder bottom there is stop pin 6 to prevent the chain
dropping into the crankcase when camshaft sprocket 1 is
removed.
Chain tension adjustment
Loosen nut 1 (Fig.2-56) of the tensioner. This releases rod 3
and the chain is tightened by means of shoe 7 (Fig.2-55) which
is loaded by spring 7 (Fig.2-56).
Turn the crankshaft 1-1.5 turns progressively. By doing that,
the tensioner spring, operating the shoe, automatically adjusts the
chain tension.
Tighten tensioner nut 1, this results in rod 3 clamped by col-
lets 8; during engine operation plunger 6 is effected only by
spring 4. The spring releases the plunger from rod 3 head, so that
the clearance between them is filled with oil that acts as a
damper when the chain strikes.
Chain renewal
Apply the handbrake, open the bonnet, remove the spare
wheel with the supporting tube and withdraw the battery.
Remove the air cleaner and close the carburettor inlet filler
with a provisional cap. Disconnect the throttle and choke cables
from the carburettor.
32
Fig2-54. Basic dimensions of the camshaft and the bearing housing