Subaru Impreza 2003, Service Manual

Page: 245 / 3610

ME(H4SO)-33
MECHANICAL
VALVE CLEARANCE
12) Similar to measurement procedures used for
#1 cylinder, measure the cylinder valve clearances
in the following sequence: #3, #2 and #4 cylinder.
NOTE:
• Be sure to set the cylinder pistons to their re-
spective top dead centers on compression stroke
before measuring valve clearances.
• To set each cylinder piston to its top dead center
on compression stroke in the following sequence:
#3, #2 and #4 cylinder, turn the crankshaft pulley
clockwise by every 180
°
at starting with #1 cylinder
piston being on top dead center on compression
stroke
.
13) After inspection, install the related parts in the
reverse order of removal.
B: ADJUSTMENT
NOTE:
Adjustment of the valve clearance should be per-
formed while engine is cold.
1) Set the #1 cylinder piston to top dead center of
compression stroke by rotating crankshaft pulley
clockwise using socket wrench.
NOTE:
When arrow mark (A) on the camshaft sprocket
(LH) comes exactly to the top, #1 cylinder piston is
brought to the top dead center of compression
stroke.
2) Adjust the #1 cylinder valve clearance.
(1) Loosen the valve rocker nut and screw.
(2) Place suitable thickness gauge.
(3) While noting the valve clearance, tighten the
valve rocker adjust screw.
(4) When specified valve clearance is obtained,
tighten the valve rocker nut.
Tightening torque:
10 N·m (1.0 kgf-m, 7.2 ft-lb)
CAUTION:
• Insert the thickness gauge in as horizontal a
direction as possible with respect to the valve
stem end face.
• Adjust the exhaust valve clearances while
lifting up the vehicle.
Valve clearance:
Intake;
0.20
±±±±
0.02 mm (0.0079
±±±±
0.0008 in)
Exhaust;
0.25
±±±±
0.02 mm (0.0098
±±±±
0.0008 in)
ME-00200
( A )
ME-00203