717 Engines

F01D4OA
1. Do not remove this plug
End bearing no. 9 can be easily removed from upper
crankcase half using the following suggested
tool (or equivalent):
– Snap-on hammer puller including:
– handle CJ93-1
– hammer CJ125-6
– claws CJ93-4.
F01J0ZA
Close puller claws so that they can be inserted
in end bearing. Holding claws, turn puller shaft
clockwise so that claws open and become firmly
tight against bearing.
Slide puller hammer outwards and tap puller end.
Retighten claws as necessary to always maintain
them tight against bearing. Continue this way until
bearing completely comes out.
F01D28A
1. End bearing
1
1
Section 04 ENGINE (2-STROKE)
Subsection 06 (ROTARY VALVE)
CLEANING
Discard all seals and O-rings.
Clean all metal components in a solvent.
Clean oil passages and make sure they are not
clogged.
Clean rotary valve shaft and inside of distance
sleeve no. 14.
INSPECTION
Rotary Valve Cover
Inspect rotary valve cover no. 1 for warpage.
Small deformation can be corrected by surfacing
with fine sand paper on a surface plate. Surface
part against oiled sand paper.
Bearings
Inspect bearings no. 8 and no. 9. Check for scoring,
pitting, chipping or other evidence of wear.
Make sure plastic cage (on bigger bearing) is not
melted. Rotate them and make sure they turn
smoothly.
Gear
Visually check gear wear pattern. It should be
even on tooth length all around. Otherwise it
could indicate a bent shaft, check deflection.
Replace gear if damaged.
Check for presence of brass filings in gear housing.
Rotary Valve Shaft Deflection
Deflection is measured with a dial gauge. Install
rotary valve shaft in crankcase half, without its
gear.
NOTE: End bearing must be in crankcase half.
Measure shaft deflection next to gear splines.
smr2004-Complete Line Up 157