Remove Breather; Check Breather; Installing Breathers - General - Briggs & Stratton Twin Cylinder L-Head Repair Manual

Horizontal crankshaft twin cylinder engines manufac-
tured before 91080000 have a breather valve in each
cover assembly and two (2) breather tubes, Fig. 6.
Vertical crankshaft twin cylinder engines have only one
breather valve and breather tube: for #1 cylinder,
Fig. 7.

Remove Breather

Before tappet and breather valve assemblies can be
removed for inspection, the air cleaner, carburetor and
intake manifold must be removed. See Section 3. On
horizontal crankshaft engines with two breathers, it is
necessary to remove the dipstick tube before the air
guide can be removed from #2 cylinder, Fig. 6.

Check Breather

If the fiber disc valve is stuck or binding, the breather
must be replaced. A .045" (1.14 mm) wire gauge
should not enter the spacer between the fiber disc
valve and body, Fig. 8.
DO NOT USE FORCE ON FIBER DISC.
Installing Breathers – General
Install new breather gasket(s) with notches facing
crankshaft, Fig. 9.
4
8
2 BREATHER
TUBES
2 BREATHERS
Fig. 6 – Horizontal Crankshaft Models
Before Date Code 91080000
BREATHER
TUBE
CYLINDER #1
BREATHER
Fig. 7 – Vertical Crankshaft Models (Typical)
.045"
(1.14 mm)
FIBER DISC
VALVE
SPARK PLUG
WIRE GAUGE
Fig. 8 – Checking Breather
TOWARD
CRANKSHAFT
Fig. 9 – Gasket Location
BREATHER
ASSEMBLY
NOTCHES
IN GASKET