Briggs & Stratton 115400, Manual

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7
Inspect Valve Stem / Valve Guide
Tolerance (All Models)
1. Measure the valve stem at the locations
illustrated in ([ A & B ] Fig. 14 ) .
Fig. 14
For listed reject dimensions: See SECTION 14-
ENGINE SPECIFICATIONS.
Inspect Valve Seat (All Models)
NOTE
: Because of the additional heat endured
by the exhaust valve, inspect the area around
the exh aust seat very carefully. Cracks or an
improper fit of the seat may not be readily
apparent. Additionally, a seat that is tight when
the engine is cold may become loose with the
heat of operation. One indication is metallic
stains around the exhaust seat.
Reface Valves and Seats (All Models)
Valve faces can be resurfaced using a
commercially available valve grindi ng tool.
Briggs & Stratton does not recommend this
practice as a high quality repair procedure.
• Replace da maged or worn valves.
For specification s relating to the engine you are
working on,
see SECTION 14- ENGINE
SPECIFICATIONS.
1. Cut valve seats with Neway Valve Seat
Cutter Kit
#19237
or
#19343
, ([ A ] Fig. 15)
to specifications listed for your engine’s
exhaust and intake seats.
• Place the proper guide pin in the valve
guide.
• Use the appropriate cutter and grind the
valve seat using the han dle and slight
pressure.
Fig. 15
Valve and seat are lapped in using Valve
Lapping Tool,
#19258
and Valve Lapping
Compound
#94150
to assure a g ood seal
between the valve face and the seat.
2. Thoroughly clean lapping compound f rom
valve seat and valve face.
If seat is wider than specific ation:
• Use a narrowing cutter.
If valve face is bu rned:
• Replace the valve.
3. Replace valve if taper depth margin ([ A ]
Fig. 16) is less than 1/64” (.4mm).