Chain Case Separation - MTD 450 Series Shop Manual

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450 Series Tillers

Chain Case Separation

1. Place the chain case on blocks or a fixture so that it
is stable and does not rest on the tine shaft or axle
shaft. The input pulley should face up.
See Figure 5.11.
2. Remove the cap screw, lock washer, and flat
washer securing the pulley to the input shaft using a
7/16" socket.
3. Slide the pulley off of the splined shaft.
NOTE: If the pulley does not slip off easily, apply
any additional force as close to the center of
the pulley as possible.
4. Before further disassembly, mark, photograph or
make notes of the fastener and bracket locations on
the chain case.
5. Clean the tine shaft and wheel axle: See Figure 5.12.
• Any dirt or corrosion will cause the shafts to bind
in their bearings as they are removed.
• There may be as little as 0.001" (0.0254 mm)
clearance between the tine shaft and the bearing
that carries it.
• There may be as little as 0.003" (0.0762 mm)
clearance between the wheel axle and the bear-
ing that carries it.
• For comparison: a human hair is usually about
0.002" (0.0508 mm). If the shafts are not shiny-
bright, they are not clean enough.
• Binding between the shafts and the bearings will
make case disassembly very difficult and time-
consuming.
6. Remove both self tapping washer head screws secur-
ing the shift cover bracket to the gear case using a 3/
8" wrench.
7. Remove the shift cover bracket. See Figure 5.13.
8. Remove both self tapping washer head screws that
hold the gear positioning bracket to the gear case
assembly using a 3/8" wrench.
NOTE: The gear positioning bracket supports the
main shaft, counter shaft, idler bracket and
the input shaft bearing. It also provides an
anchor point for the clutch cable
9. Remove the hex nuts and Belleville washers from the
counter shaft and the wheel speed reducing gear
shaft using an 11/16" wrench.
30
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Input pulley
Figure 5.11
Figure 5.12
Shift cover bracket
Figure 5.13