Briggs & Stratton Twin Cylinder L-Head, Руководство по ремонту

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3
After the bearing has been removed, rough spots on
the journal should be polished with emery cloth (500
grit). Break down new emery cloth by rubbing several
times over the edge of a piece of steel before using for
polishing.
Polish crankshaft until polish lines are uniform over
entire journal, Fig. 4. It is important that crankshaft
journal be thoroughly cleaned. Wash journal with a
solvent such as kerosene to remove emery residue.
Fig. 4 – Polish Journal
POLISH
LINES
Install Ball Bearings
1. Heat bearing in hot oil (250
°
F (120
°
C) max).
Bearing must not rest on the bottom of the pan in
which it is heated.
2. Place crankshaft in vise with bearing side up.
When bearing is quite hot it will become a slip fit on
the bearing journal.
3. Grasp bearing with the shield down (if equipped)
and thrust it down on the crankshaft, Fig. 5. The
bearing will tighten on the shaft while cooling. DO
NOT QUENCH.
NOTE: Engines manufactured after 1992 and
service replacement ball bearings are not
equipped with a bearing shield.
If ball bearing is equipped with a bearing shield, install
bearing so that shield faces crankshaft crankpin.
Fig. 5 – Installing Ball Bearing
HOT
BEARING
CRANKSHAFT
CRANKSHAFT END PLAY
Crankshaft end play is .002” (.05 mm) to .026” (.66
mm) on vertical crankshaft engines and .004” (.10 mm)
to .012” (.30 mm) on horizontal crankshaft engines
with one .015” (.4 mm) gasket in place. If end play is
less than .002” (.05 mm), which could be the case if a
new crankcase cover or sump is used, additional
gaskets .005” (.13 mm), .009” (.23 mm) or
.015” (.4 mm) may be added to obtain correct end play.
If end play is more than .026” (.66 mm) for vertical
crankshaft engines or .012” (.30 mm) on horizontal
shaft engines, with one .015” (.4 mm) gasket in place,
install thrust washer, Part #222951, Fig. 6. Install
thrust washer on PTO end of crankshaft, plain bearing
engines or magneto end of crankshaft on engines with
ball bearing on PTO side only. Then adjust end play as
described in previous paragraph.
NOTE: Thrust washer part #222951 cannot be
used on double ball bearing engines.
Vertical crankshaft engines manufactured after
93122000 are equipped with a .030” (.76 mm) thinner
timing gear. If a cylinder, crankshaft or sump is being
replaced it may be necessary to change the timing
gear if the correct end play cannot be obtained with
standard gaskets or a thrust washer. Order timing gear
Part #262989.
Fig. 6 – Correcting Crankshaft End Play
#222951
THRUST
WASHER