Thermo King SGCO 3000, Руководство пользователя

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Engine Maintenance
111
Adjusting Engine Valve
Clearance
Valve clearance should be checked as required. It
is very important that valves be adjusted to the
correct specifications for satisfactory engine
operation. Insufficient valve clearance will result
in compression loss and misfiring of cylinders.
This will result in burned valves and seats.
Excessive valve clearance will result in noisy
valve operation and abnormal wear of the valves
and rocker arms. The intake and exhaust valves
are adjusted with the valve in the closed position.
Figure 88: Adjusting the Valve Clearance
Complete the following steps to adjust the engine
value clearance.
1. Remove the rocker arm cover.
2. Remove the round cover (plug) from the
timing mark access hole on the front of the
bell housing.
3. Place the engine at top dead center of the
compression stroke for the number one
cylinder.
a. Rotate the engine in the normal direction
of rotation (clockwise viewed from the
water pump end). Rotate the engine until
the 1-4 timing mark on the flywheel lines
up with the index mark in access hole.
b. Check the rocker arms on the number one
cylinder.
c. If the rocker arms are loose, the engine is
at top dead center of the compression
stroke for the number one cylinder.
d. If the rocker arms are tight, the engine is at
top dead center of the exhaust stroke for
the number one cylinder. Rotate the engine
360 degrees to place the engine at top dead
center of the compression stroke for the
number one cylinder.
4. Check the valve clearance of both valves for
the number one cylinder with a feeler gauge.
Also check the valve clearance for the intake
valve for the number two cylinder, and the
exhaust valve for the number three cylinder.
The clearance for both the intake and exhaust
valves should be 0.15 to 0.25 mm (0.006 to
0.010 in.).
NOTE: Check to make sure that the valve
stem cap is in good condition and is
positioned squarely on the top of the valve
stem. Replace the valve stem cap if it shows
significant wear.
5. Loosen the locknut and adjust the valves as
required by turning the adjustment screw.
6. Hold the adjustment screw while tightening
the locknut.
7. Recheck the valve clearance.
WARNING: Loosen all of the injection
lines at the injection nozzles to prevent the
possibility of the engine firing while it is
being rotated.
AXA0304
1. Timing Mark
2. Top Dead Center Mark for Cylinders 1 and 4
3. Top Dead Center Mark for Cylinders 2 and 3
Figure 89: Timing Marks
AJA2085
1
1
3
2