Briggs & Stratton Vanguard 10V300, Руководство по ремонту

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Check/Adjust Valve Clearance
NOTE: For best results, check valve clearance with the
engine cold.
1. Remove spark plug wire from spark plug terminal.
2. Thoroughly clean area around spark plug to keep
dust and dirt out of the combustion chamber.
3. See Figure 16. Remove spark plug ( A ) from cylinder
head using the 5/8 inch Spark Plug Wrench (Part No.
19576S).
4. Remove four hex flange screws ( B ) to release valve
cover ( C ).
5. Remove and discard valve cover gasket ( D ).
6. Move piston 1/4 inch (6 mm) past Top Dead Center
(TDC) of the compression stroke. Proceed as follows:
A. While rotating flywheel end of crankshaft (
E ) by
hand in the direction of engine rotation, watch the
rocker arms to determine the action of the valves.
After the exhaust valve closes, the intake valve
begins to open.
B. When the intake valve closes (so that both valves
are closed with the rocker arms loose), insert a
wooden dowel ( F ) through the spark plug hole
until seated at the top of the piston ( G ).
C. Rotate engine in the same direction until the
piston pushes the wooden dowel to its highest
point. This is TDC of the compression stroke.
D. Place a mark on the wooden dowel that is even
with the machined surface at the top of the spark
plug hole. Make a second mark 1/4 inch (6 mm)
above the first.
E. Rotate engine in the same direction until the
second mark on the wooden dowel is even with
the machined surface at the top of the spark plug
hole. Remove wooden dowel.
7. Insert feeler gauge between rocker arm and exhaust
valve stem. Verify that exhaust valve clearance is
0.006-0.008 inches (0.15-0.20 mm).
8. If adjustment is necessary to obtain proper clearance,
proceed as follows:
A. Loosen set screw (
H ) and turn rocker ball nut ( I )
as necessary.
B. Holding rocker ball nut to prevent rotation, tighten
set screw to 60-80 lb-in (6.8-9 N-m).
C. Check valve clearance again to verify that rocker
ball did not move when set screw was tightened.
9. Insert feeler gauge between rocker arm and intake
valve stem. Verify that intake valve clearance is
0.004-0.006 inches (0.10-0.15 mm). If adjustment is
necessary, see step 8.
10. Remove old gasket material from valve cover and
cylinder head flanges. Gasket material left on sealing
surfaces will cause leaks.
11. Install new valve cover gasket onto valve cover.
12. Start four hex flange screws to fasten valve cover to
cylinder head. Alternately tighten screws to 70-90 lb-
in (7.9-10.2 N-m) using a crosswise pattern.
13. Install spark plug into cylinder head and finger tighten
until snug. Tighten spark plug to 140-200 lb-in
(15.8-22.6 N-m).
14. Install spark plug wire onto spark plug terminal.
16
Not for
Reproduction