Ingersoll-Rand 3IRH2N, Руководство по ремонту

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(4) Measuring and adjusting Valve Clearance
Make measurement and adjustment while the engine
is cold.
(a) Valve clearance measurement
1) Remove the bonnet above cylinder head.
2) Set the No.1 cylinder in the compression TDC
Turn the crankshaft to bring the piston of the
No.1 cylinder to its compression top dead center
while watching the rocker arm motion, timing
scale and the top mark position of the crankshaft
pulley.
(Position where both the intake and exhaust
valves are closed.)
Notes:
The crankshaft shall be turned clockwise as seen
from the radiator side.
The No.1 cylinder position is on the opposite side
of the radiator and the ignition order shall be 1-3-4-2-
1 at 180
°
intervals.
Since the intake and exhaust valve rocker arms are
operated the same and there is a clearance between
the arm and valve generally at the top dead center,
the position can be checked by means of the play
when the arm head is held with a hand. Also see that
the crankshaft pulley top mark is positioned at zero on
the timing scale. If there is no valve clearance,
inspection in the disassembled state is necessary
since the valve seat may be worn abnormally.
3) Valve clearance measurement
In case of 2-valve cylinder head insert a
thickness gage between the rocker arm and
valve cap, and record the measured valve
clearance.
In case of 4-valve head insert a thickness gage
between the rocker arm and the valve bridge,
and record the measured valve clearance.
(Use it as the data for estimating the wear state.)
4) Adjusting other cylinders
In case of 4-cylinder engines, turn the crankshaft
180° and make adjustment for the No.3 cylinder.
Then adjust the No.4 and No.2 cylinders in this
order.
The cylinder to be adjusted first does not have to be
the No.1 cylinder. Select and adjust the cylinder
where the piston is the nearest to the top dead
center after turning, and make adjustment for other
cylinders in the order of ignition by turning the
crankshaft 180° each time.