Assembling Oil Seal; Assembling Piston Rings On Piston - Bosch PB-650 Service Manual

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8-14 Assembling oil seal

Dust lip
Oil seal section

8-15 Assembling piston rings on piston

( 1 )
( 2 )
( 3 )
(A)
(B)
ENGINE
Seal lip
(B)
(A)
Cut view (1)
Cut view (2)
Cut view (3)
(C)
(D)
1. Apply lithium based grease on dust lip and seal
lip of oil seal to avoid damage of lips while inserting
crankshaft into the oil seal.
2. Lubricate the circumference of oil seal with alco-
hol or thinner.
3. Push oil seal (A) down 1 mm from boss edge
using oil seal tool 897726-21430 (B) for both starter
side seal and fan side seal.
4. Install woodruff key on magneto rotor side crank-
shaft.
NOTE : The 1st piston ring and the 2nd piston ring
are not interchangeable. If the 2nd piston ring is in-
stalled in 1st ring groove, cylinder can not be
assembled on the piston.
1. Assemble the 2nd ring (A) firstly, while meeting
ring-ends with locating pin of the 2nd ring groove (B).
2. Assemble 1 st ring (key-stone ring) (C), while
meeting ends of 1st ring with locating pin of the 1st
ring groove (D).
NOTE : In case of assembling the key-stone ring
without meeting the ends with the locating pin and
rotated the ring to meet with the locating pin after
assembling the ring, the ends might scratch on the
groove as shown. If the scratch is made, friction of
piston-movement becomes bigger.
PB-650
PB-750
1mm