Belarus 1221.2, Руководство оператора

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BELARUS-1221.2/1221V.2/1221.3 Scheduled maintenance
257
After every 500 service hours
Perform the operations of the previous MS
and the following ones:
Operation 22. Check and adjust valve
clearances in the engine
Note: Check the clearances on a cold
engine after checking the cylinder head
bolt tightening (Operation 37).
• Remove the cover caps from the
cylinder heads.
• Check tightening of the bolts and nuts
fastening the rockers arm shaft brackets
(60 to 90 N•m).
• Turn the crankshaft until the valves
overlap in the first cylinder (the inlet
valve starts opening, and the exhaust
valve ends closing).
• Adjust the clearances in the 3, 5, 7, 10,
11 and 12 valves (counting from the
fan).
ATTENTION! The clearance between
the ends of the valve rods (5) and the
arm shaft strikers (4) must be 0.25 to
0.30 mm for the inlet valves and 0.40 to
0.45 mm for the exhaust valves.
• Crank the crankshaft to 360°, making an
overlap in the sixth cylinder, and adjust
clearances in the 1, 2, 4, 6, 8 and 9
valves.
• To adjust the clearance, release the
locknut (1) of the adjustment screw (2)
and using a key and screwdriver set the
necessary clearance by the probe (3).
After setting the clearance, tighten the
locknut (1) and re-check the clearance
with the probe.
• After adjusting, install the removed
parts to their places.