Cylinder Head; Disassembly; Cleaning; Inspection - Briggs & Stratton 130G00 Repair Manual

Disassembly

1. Pack shop towels into the combustion chamber and
place cylinder head on bench with the combustion
chamber side down.
2. Remove valve cap from exhaust valve.
3. See Figure 51. Using thumb pressure, press down on
valve spring retainer to disengage from valve stem
groove. Guide valve stem into larger offset hole in valve
spring retainer and then relieve valve spring tension.
4. Remove valve spring retainer and valve spring.
5. Slide exhaust valve from valve guide.
6. Mark the bottom of the valve to indicate the valve guide
from which it was removed. Tag the valve cap, valve
spring retainer, and valve spring, so that they are
installed on the same valve at time of assembly.
7. Repeat steps 2-6 on the intake valve.
NOTE: Valve cap is not present on 13U100 and 13U200
models.
8. Remove valve stem seal/washer from cylinder head.
Discard valve stem seal/washer.
NOTE: Models 13U100 and 13U200 use a different
style valve stem seal. Remove and discard.
51

Cleaning

1. See Figure 52. Using a plastic scraping tool, carefully
remove old gasket material from the cylinder head.
Gasket material left on sealing surfaces will cause leaks.

CYLINDER HEAD

52
2. Remove all carbon deposits from combustion chamber
and machined surfaces of cylinder head. Exercise
caution to avoid removing any metal material. For best
results, use an air tool with a worn fine wire brush.
Scraping may result in scratches or nicks.
3. To soften stubborn deposits, soak the cylinder head in
a suitable chemical solution or other carbon and gum
dissolving agent. Repeat steps 2-3 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.
4. Thoroughly clean the cylinder head, valves, valve
springs, valve spring retainers, valve caps, tappets,
pushrods, 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.
6
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