Gravely 991091 ZT HD60 Owner's/Operator's Manual page 28

4. Remove short mower belt from right
blade spindle and from deck. Idler pivot
bolt must be loosened slightly to gain
clearance to remove belt from under
idler pulley (Figure 19).
5. Arrange new mower belt(s) on deck
(short belt first). Retighten short mower
belt idler pivot bolt. Install belts on
sheaves. Put belts onto center sheave
last.
NOTE: The PTO idler spring length range is
12.25 – 12.5 in. (31 – 31.8 cm) measured at
a 3 in. (7.62 cm) cutting height. Adjust the
idler spring length as needed, see Figure 20.
6. Replace belt covers and return foot
board to closed position.
3
5
1
6
1. PTO Mower Belt
2. Mower Drive Belt
3. Springs
4. Mower Drive Belt Idler
5. PTO Mower Belt Idler
6. Mower Clutch Sheave
7. Center Sheave
Figure 19
2
4
7
GB - 28
PTO Idler Spring Length
Measure PTO
idler spring
length here.
The PTO idler spring length range is
12.25 – 12.5 in. (31 – 31.8 cm) measured
at a 3 in. (7.62 cm) cutting height. Adjust
as necessary.
Figure 20
Replacing the Hydro Pump Belt
1. Properly stop and park unit (See
Operation on page 14).
2. Remove the PTO belt from the mower
clutch sheave (See Replacing Mower
Belts on page 27).
CAUTION: Use care when
releasing idler spring tension.
Keep body parts well away from
idlers when performing this
operation.
3. Slowly release the tension on the hydro
pump belt idler until all the tension is
removed from the springs.
4. Remove old hydro pump belt from right
hand hydrostat sheave first (Figure 21).
5. Install new hydro pump belt by
positioning belt on sheaves. Put belt
onto right hand hydrostat sheave last.
6. Replace long mower belt on mower
clutch sheave. See Replacing Mower
Belts on page 27.
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