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ENG
 
VALVES AND VALVE SPRINGS 
ASSEMBLY AND INSTALLATION  
1. Apply: 
l 
Molybdenum disulfide oil
(onto the valve stem and valve stem
seal)
2. Install: 
l 
Valve stem seats  
l 
Valves 
l 
Valve springs 
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Valve spring retainers
NOTE:
 
l 
Make sure that each valve is installed in its
original place, also referring to the embossed
mark as follows.
Intake: “G”
Exhaust: “L” 
l 
Install the valve springs with the larger pitch 
a  
 facing upwards. 
b  
Smaller pitch
New
 
3. Install: 
l 
Valve cotters
NOTE:
 
While compressing the valve spring with a
valve spring compressor and attachment   
1 
install the valve cotters. 
Valve spring compressor:
YM-4019/90890-04019 
4. To secure the valve cotters onto the
valve stem, lightly tap the valve tip with a
piece of wood.
CAUTION:
 
Hitting the valve tip with excessive force 
could damage the valve.