Simplicity RTH Series Operator's Manual page 46

Adjustments
6. Disengage mower PTOto arrange thebladesso they are
facing front to back, parallel with the tractor. Engage
mower PTO again.
7. Measure the distance to the ground from the front tip of
the left blade and the rear tip of the right blade. The
measurements should be equal. If they are not, proceed
as follows.
NOTE
One full turn of clevis will equal about 1/8 inch.
8. Remove the cotter pins and pins (B) from the hitch
clevises (C). Loosen the two nuts (A). Turn each clevis
an equal number of turns in the same direction. Shorten
the hitch rods to raise the front of the mower or lengthen
the hitch rods to lower the front of the mower.
Figure 39. Leveling Mower
A. Jam Nuts
B. Pins
C. Hitch Clevises
D. Mower Levelling Rod
E. Cotter Pin
F. Suspension Arm
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