Exhaust Valve - Kohler CH18 Service Manual

Disassembly/Inspection and Service
Inspection and Service
Valve Details

EXHAUST VALVE

E
G
H
Dimension
A Seat Angle
B Insert O.D.
C Guide Depth
D Guide I.D.
E Valve Head Diameter
F Valve Face Angle
G Valve Margin (Min.)
H Valve Stem Diameter
After cleaning, check fl atness of cylinder head and corresponding top surface of crankcase, using a surface plate or
precision straight edge and feeler gauge. Maximum allowable out of fl atness is:
0.076 mm (0.003 in.) for 77 mm and 80 mm bores;
0.1 mm (0.004 in.) for 83 mm bore.
Carefully inspect valve mechanism parts. Inspect valve springs and related hardware for excessive wear or distortion.
Check valves and valve seat area or inserts for evidence of deep pitting, cracks, or distortion. Check clearance of
valve stems in guides.
Hard starting or loss of power accompanied by high fuel consumption may be symptoms of faulty valves. Although
these symptoms could also be attributed to worn rings, remove and check valves fi rst. After removal, clean valve
heads, faces, and stems with a power wire brush.
Then, carefully inspect each valve for defects such as a warped head, excessive corrosion, or a worn stem end.
Replace valves found to be in bad condition.
96
F
C
D
D
Intake
89°
36.987/37.013 mm (1.4562/1.4572 in.)
4 mm (0.1575 in.)
7.038/7.058 mm (0.2771/0.2779 in.)
33.37/33.63 mm (1.3138/1.3240 in.)
45°
1.5 mm (0.0591 in.)
6.982/7.000 mm (0.2749/0.2756 in.)
KohlerEngines.com
INTAKE VALVE
F
B
A
EXHAUST
INSERT
INTAKE
INSERT
A
B
Exhaust
32.987/33.013 mm (1.2987/1.2997 in.)
6.5 mm (0.2559 in.)
7.038/7.058 mm (0.2771/0.2779 in.)
29.37/29.63 mm (1.1563/1.1665 in.)
1.5 mm (0.0591 in.)
6.970/6.988 mm (0.2744/0.2751 in.)
E
G
H
89°
45°
24 690 06 Rev. P