Inspection And Repair - Briggs & Stratton 272147 Repair Manual

TM
Vanguard Twin-Cylinder OHV Liquid-Cooled Engine
Section 4 - Engine Overhaul
CYLINDER HEAD INSPECTION AND
REPAIR
Disassemble Cylinder Head
1. Place a shop rag or short section of rubber fuel
line under valves inside combustion chamber to
hold valve in place while compressing spring.
2. Thread rocker arm support screw into cylinder
head a few turns and compress spring with valve
spring compressor, Tool
the following:
a. Valve spring retainer locks
b. Valve spring retainers
c. Valve springs
d. IN and EX valves
Fig. 80
3. Remove and discard valve stem seals, Fig. 81.
Fig. 81
, Fig. 80. Remove
#19347
Inspect And Repair
1. Check cylinder head. Be sure all gasket material is
removed from surfaces before checking. Use a
gasket scraper if necessary.
a. Inspect cylinder head for cracks or damage.
b. Use a surface plate or straight edge and check
cylinder head mounting surface for distortion.
If mounting surfaces are distorted more than .004" (0.1
mm), the cylinder head must be replaced, Fig. 82.
It is not recommended that cylinder head mounting
surfaces be resurfaced.
Fig. 82
2. Check valve guide bushings for wear using reject
gauge, Tool
#19382
a. Replace valve guide if gauge enters guide 1/4"
(6 mm) or more.
Fig. 83
, Fig. 83.
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