Briggs & Stratton Twin Cylinder L-Head Repair Manual page 131

ENGINE DISASSEMBLY
Drain oil and remove engine from equipment. Remove
exhaust system, air cleaner assembly, intake manifold
and carburetor assembly. See Section 3. Remove
blower housing, air guides, cylinder shields, cylinder
heads and valves. See Section 5. Remove flywheel
and armature. See Section 2.
1. Remove the following parts, Fig. 1.
a. Alternator
b. Starter Motor
c. Backplate
2. Remove engine base (horizontal shaft).
Remove cylinder cover plate (vertical shaft).
3. Remove any carbon or ridge at the top of cylinder
bores to prevent breaking rings when removing
piston and connecting rod assemblies.
4. Remove No. 2 connecting rod cap and push
connecting rod and piston assembly out of cylin-
der, Fig. 2.
a. Reassemble cap to rod to prevent inter-
changing.
5. Repeat for other cylinder.
NOTE: Remove any rust, paint or burrs from PTO
end of crankshaft before removing crank-
case cover or sump to prevent damaging
bearing.
Remove Crankshaft – Plain Bearing Models
1. Remove crankcase cover or sump.
2. Rotate crankshaft until timing marks line up, Fig. 3.
3. Remove camshaft making sure valve tappets are
clear of lobes.
4. Remove crankshaft.
a. Remove tappets.
NOTE: Support crankshaft during removal to
prevent damage to magneto bearing.
Remove Crankshaft – Ball Bearing Models
1. Remove crankcase cover.
2. Rotate crankshaft until timing marks line up.
a. Timing mark on crankpin and cam gear will be
aligned when #2 crankpin is rotated to approx-
imately 10 o'clock position, Fig. 4.
3. Pull crankshaft and cam gear out until cam gear
teeth disengage teeth on crankshaft gear.
4. Then, remove camshaft making sure tappets are
clear of lobes.
5. Remove crankshaft.
a. Remove tappets.
CLEAN ALL SURFACES OF GASKET MATERIAL. REMOVE OIL SEALS AND THOROUGHLY CLEAN COM-
PONENTS IN SOLVENT. ORGANIZE COMPONENTS, KEEPING PARTS WHICH ARE AN ASSEMBLY TOGETHER.
2
9
a
Fig. 1 – Remove Alternator, Starter & Backplate
Fig. 2 – Remove Connecting Rod & Piston
CRANKSHAFT
TIMING
MARK
Fig. 3 – Remove Crankshaft – Plain-Bearing Models
TIMING MARK
ON
CAMSHAFT
CRANKPIN
TIMING MARK
Fig. 4 – Remove Crankshaft – Ball Bearing Models
c
b
CAM-
SHAFT
TIMING
MARK
(DOT)