Simplicity CFC Series Operator's Manual page 53

Adjustments
BELT CLEARANCE (3-Blade Mowers)
Sufficient clearance (1" minimum) must be maintained
between the long side of the mower drive belt and the flat
idler pulley (B, figure 37) to prevent rubbing during
operation. To increase clearance, position the V-idler pulley
(D) in the forward most hole.
Spring tension on the belt should prevent slippage without
overtensroning the belt. If the spring tension on the idler
pulley assembly is too strong after moving idler pulley (D),
spring mounting bolt can be moved in one of three hole
locations (£).
If additional clearance is required, it is acceptable to shim the
PTO pulley (A) outward with washer{s).
Rgure 37. Belt Clearance
A. PTO Idler Pulley
B. Flat Idler Pulley
C. Mower Drive Pulley
D. V-ldler Pulley
£. Spring Mounting Holes
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