Checking The Valve Guide; Replacing The Valve Guide - SELVA MARINE Kingfish 25 Service Manual

POWR
b
Valve stem diameter b:
Intake:
5.475–5.490 mm (0.2156–0.2161 in)
Exhaust:
5.460–5.475 mm (0.2150–0.2156 in)
4. Measure the valve stem runout. Replace
if above specification.
Valve stem runout:
Intake and exhaust:
0.010 mm (0.0004 in)

Checking the valve guide

Before checking a valve guide, make sure to
check the valve.
1. Measure the valve guide inside diameter
a. Replace if out of specification.
a
7-41
Power unit
Valve guide inside diameter a:
Intake and exhaust:
5.500–5.512 mm (0.2165–0.2170 in)
2. Calculate the valve-stem-to-valve-guide
clearance as follows. Replace the valve
guide if out of specification.
Valve-stem-to-valve-guide clearance
= valve guide inside diameter –
valve stem diameter:
Intake:
0.010–0.037 mm (0.0004–0.0015 in)
Exhaust:
0.025–0.052 mm (0.0010–0.0020 in)

Replacing the valve guide

After replacing the valve guide, check the
valve seat contact area.
1. Remove the valve seal.
2. Remove the valve guide 1 from the
combustion chamber side using the spe-
cial service tool 2.
1
Valve guide remover/installer 2:
90890-06801
3. Install a new valve guide 3 from the
camshaft side to the specified position a
using the special service tool 2.
2