Pulley Alignment And Travel - MTD 450 Series Shop Manual

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450 Series Tillers

Pulley alignment and travel

1. If there is question about pulley alignment, a
straight-edge may be used to check them.
2. Input pulley removal: See Figure 2.6.
2a. Put the chain case in Neutral and rotate the
input pulley to make a visual check for run-out.
2b. A single bolt holds the input pulley to the input
shaft of the chain case. If there is run-out,
remove the pulley and inspect it to determine
if the pulley sheave is bent, the input shaft is
bent, or if the splined joint between the two
has been damaged.
3. Idler pulley:
3a. When the clutch is released, the idler pulley
bracket should rest against the bracket that
supports the belt cover.
3b. The idler pulley belt keeper is located by the
same bolt that holds the pulley. A bend on the
bottom edge hooks around the idler pulley
bracket to keep the belt keeper properly ori-
ented. See Figure 2.7.
3c. The arm that supports the idler pulley mounts
on a shoulder nut behind the input pulley.
Confirm that the arm moves freely on the pivot
point. Confirm that the arm is not bent, mis-
aligning the pulley.
4. Crankshaft pulley: See Figure 2.8.
4a. The two-piece crankshaft pulley is held
against a shoulder on the engine crankshaft
by a single bolt.
4b. One half of the pulley has a short shoulder,
the other has a long shoulder. The long shoul-
der should be furthest from the engine. If they
are reversed, the belt will chafe at an angle
between the pulleys.
4c. The pulley half that is closer to the engine has
a key formed into it.
4d. The two pulley halves have a serrated joint to
transfer drive torque from the inner half to the
outer half.
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Figure 2.6
Interlock pin
Belt keeper
Idler pulley
bracket
Figure 2.7
Both sheaves on
the crankshaft
Figure 2.8
Input shaft
Input pulley
Sheaves separated