Briggs & Stratton 115400, Manual

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BREATHER SYSTEMS
Briggs & Stratton engines use a breather valve to
maintain and control a pulsating vacuum in the
cylinder or sump. The vacuum helps to control oil
leakage past piston rings, valve guides, oil seals,
governor lever shaft and gasket s.
The breather valve is a fiber disc or reed that
closes on the pisto n's up stroke and opens on
the piston's down stroke.
Breather System
(050000, 085400, 086400, 115400,
117400, 118400, 138400, 185400,
235400, 245400)
Remove Va lve Cover
1. Remove scr ews ( A ) fr om valve cover, Fig.
22.
2. Remove valve cover and gasket(s).
Fig. 22
The brea ther components are built into the valve
cover for the models listed. They consist of (
A ) a
port for the breather hose, ( B ) a reed and valve
assembly inside the cover and ([ C ] Fig. 23) a
relief hole to balance cylinder pressures in case
the breather asse mbly sticks or binds.
Fig. 23
To check breather assembly:
1. Cover relief hole with thumb.
2. Blow into the breather port hole - air
should not pass.
3. Inhale through the breather hose port - air
should pass freely.
Replace valve cover if any binding or sticking is
discovered.
Remove/Replace Breather System
(104700)
1. Remove air cleaner cover, flywhe el brake
cover (if equip ped), blower housin g, rope
starter, and flywheel.
SEE SECTION 1-
AIR CLEANER SERVICE.
Fig. 24