Assembly
group
7
CRANKCASE, CRANKSHAFT-RM
252
Special JLO Tools
Puller 444.31.807.000 (10)
Pair of half shells
444.31.072.000 (10)
Retaining ring
444.31.071.100 (10)
DISASSEMBLY
7.1. 1
2
3
4
5
6
7
8
9
10
ASSEMBLY
7.2. 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Loosen bolts (3) and remove spring washers (4).
Pull crankcase pto side (2) off crankshaft (5). Slide fit of ball bearing (8) and
crankcase (5) allows disassembly without heating up. Discard gasket (22).
Remove washer (7) and complete thrust bearing assembly (11) from the crankshaft
(5).
Remove balls (13).
Heat crankcase half starter side (1) to approx. 100°C (212°F).
Lift crankcase assembly (1),
so
that pto shaft end is clear of the work bench, and
gently tap crankshaft with plastic hammer out of the crankcase. Remove shim(s) (10)
and seal (19).
To remove ball bearing (9) from crankshaft
(5)
use bearing puller assembly (12).
Loosen Loctited screws (17) and remove governor fork (18).
Pull governor shaft (16) out of case (2). Remove washers (15) and knock out small
oil seal (14).
Heat housing pto side (2) to approx. 100°C (212°F), and tap out ball bearing (8).
Remove seal (19) (illustr. I).
Slightly lubricate new oil seals (19). Insert seals with oil seal installation tool
into both crankcase halves (1+2). Sealing lips facing' the inside
of
the crankcase.
Place heat shield over oil seal (19) and heat crankcase pto side (2) to approx.
100°C (212°F). Use ball bearing driver and place ball bearing (8) into crankcase.
Slightly lubricate governor shaft (16). and fit thrust washers (15) into crankcase
(2) (illustr. I).
Use locking compound when tightening screws (17) and fit governor fork (18) on
governor shaft (16). (illustr. II).
Knock oil seal (14) into its position. Use slip cone
(20),
and driver (21)
(illustr. V).
Warm ball bearing (9) to approx.
80°C
(175°F) and drive it on the crankshaft
(starter side) by ball bearing driver. (Drive only on
inner
bearing race).
Fit governor balls (13) into bores of pto crankweb.
Mount three piece thrust bearing (11). (see illustr. III).
Mount shim (7) with recess facing towards crankweb.
placed slide fitted on crankshaft.
Insert sub-assembled crankshaft
(5)
into crankcase pto side (2) (Ball bearing is
Lightly grease new gasket (22) with general purpose grease, and place in position
on crankcase (2).
Limit axial play of crankshaft (5) by using shims (10), thickness 0.2
mm
(.008 in.)
(illustr. IV)
.
Measuring plane for depth gauge: upper ball bearing edge to crankcase sealing face
with gasket (22) in place (illustr. IV). Any difference between measured result and
required measure (30.1
-
30.2
mm/
1.185-1.189 in.) has to be compensated with shims
(10). Thickness of shims 0.2
mm
(.008 in.) (See table
on
page 24).
Place heat shield over oil seal (19), Heat crankcase starter side (1) to approx.
100°C (212°F), and mount it (1) on crankcase half, pto side (2).
NOTE:
Make sure that seals (19) will not be damaged. (Use approximate slip cone).
Ensure both crankcase halves (1+2) are properly aligned and install screws (3) with
spring washers (4) fingertight.
Tighten screws of crankcase (3).
Re-check mounting surface for cylinder. Cut off overhanging gasket part (22).
After mounting cylinder (see description on page 21) tighten crankcase bolts (3).
Torque 90-100 Nm (66.4-73.7 ft/lbs).
Turn crankshaft (6) by hand to ensure free moving. If crankshaft will not turn
freely, tap each end of crankshaft lightly with a plastic hammer.
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