Briggs & Stratton Vanguard 10V300, Руководство по ремонту

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a worn fine wire brush. Scraping may result in
scratches or nicks.
2. To soften stubborn deposits, soak the cylinder
head in a suitable chemical solution or other carbon
and gum dissolving agent. Repeat steps 1-2 as
necessary.
NOTE: Do not use glass or sand to bead blast
surfaces exposed to the engine oil. Bead blasting
materials become lodged in the pores of the casting
where they cannot be removed through ordinary
cleaning methods. Only after the engine is put to
use will heat expansion cause this material to be
released, and the resulting oil contamination will
accelerate wear and lead to engine failure.
3. Thoroughly clean the cylinder head, valves, valve
springs, valve spring retainers, valve caps, tappets,
push rods, and rocker arms in a non-volatile cleaning
solution or solvent. Follow up with a thorough wash
in hot soapy water. Blow dry with low pressure
compressed air.
Inspection
Cylinder Head
1. Check for scratches and nicks on all gasket sealing
surfaces.
2. Check condition of spark plug threads. If necessary,
soften deposits with penetrating oil and clean out with
a thread chaser.
3. Check the cylinder head to cylinder mating surface for
warpage or distortion. Discard the cylinder head if any
low spot is 0.002 inches (0.05 mm) or more. Proceed
as follows:
A. See A of Figure 54. With the combustion
chamber side facing up, set a straightedge
diagonally across the length of the cylinder head
gasket surface.
B. Slide a feeler gauge beneath the straightedge to
check for warpage.
C. Check the opposite diagonal to verify that the
gasket surface is flat.
D. See B of Figure 54. Set a straightedge vertically
across the length of the cylinder head gasket
surface. Use feeler gauge to check for warpage.
Repeat step on opposite side.
54
E. See C of Figure 54. Set a straightedge
horizontally across the length of the cylinder head
gasket surface. Use feeler gauge to check for
warpage. Repeat step on opposite side.
4. Repeat the 6 point check outlined under step 3 to
check for warpage or distortion of the cylinder head
to valve cover mating surfaces. Be sure to check
both the cylinder head and valve cover. Discard the
cylinder head or valve cover if any low spot is 0.002
inches (0.05 mm) or more.
5. Visually inspect the cylinder head for cracks or
discoloration due to excessive heat. Replace cylinder
head if either of these conditions are found.
6. Verify that breather hole, and intake and exhaust
ports are clean and open.
Valve Guides
1. Inspect external surface of valve guides for cracks
(particularly the combustion chamber side). Replace
the cylinder head if cracks are found.
Not for
Reproduction