Cylinder Head And Valves - wsm wg972-e4 Workshop Manual

WG972-E4, WSM

(2) Cylinder Head and Valves

Top Clearance
1. Remove the cylinder head.
2. With the piston at TDC, use grease to affix three or four
plastigauges of a diameter 1.5 mm (0.059 in.) × 5.0 to 7.0 mm
(0.20 to 0.27 in.) long to the crown of the piston; keep the
gauges away from the intake valve and combustion chamber
fittings.
3. Take the piston to an intermediate position, install the cylinder
head and tighten the head bolts to the specified torque.
4. Turn the crankshaft so the piston goes through TDC.
5. Remove the cylinder head and measure the thickness of the
plastigauges.
6. If they are out of spec, check the oil clearance of the crank pin
journal and piston pins.
Top clearance Factory specification
Tightening torque Cylinder head screws
(1) Plastigauge
Cylinder Head Surface Flatness
1. Clean the cylinder head surface.
2. Place a straightedge on the cylinder head's four sides and two
diagonal as shown in the figure.
3. Measure the clearance with a feeler gauge.
4. If the measurement exceeds the allowable limit, correct it with a
surface grinder.
IMPORTANT
• Be sure to check the valve recessing after correcting.
Cylinder head surface
Allowable limit
flatness
Cylinder Head Flaw
1. Prepare an air spray red check.
2. Clean the surface of the cylinder head with the detergent (2).
3. Spray the cylinder head surface with the red permeative liquid
(1). Leave it five to ten minutes after spraying.
4. Wash away the red permeative liquid on the cylinder head
surface with the detergent (2).
5. Spray the cylinder head surface with the white developer (3).
6. If flawed, it can be identified as red marks.
(1) Red Permeative Liquid
(2) Detergent
1-S41
ENGINE
1.15 to 1.35 mm
0.0453 to 0.0532 in.
38 to 42 N·m
3.8 to 4.3 kgf·m
28 to 31 lbf·ft
(2) Scale
9Y1211108ENS0063US0
0.05 mm
0.002 in.
9Y1211108ENS0064US0
(3) White Developer
9Y1211108ENS0065US0
KiSC issued 07, 2015 A