VanguardTM 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 #19347, Fig. 80. Remove the following: a. Valve spring retainer locks b. Valve spring retainers c. Valve springs d. IN and EX valves
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
Fig. 80
2. Check valve guide bushings for wear using reject , Fig. 83. gauge, Tool #19382 a. Replace valve guide if gauge enters guide 1/4” (6 mm) or more.
3. Remove and discard valve stem seals, Fig. 81.
Fig. 81
Fig. 83
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