Wallenstein BXT4224 Operator's Manual page 52

Service and Maintenance
9.9.2 Set the Drive Belt Tension
Check the drive belt tension after every 100 hours of
operation.
1. Press on the top centre of the rotor drive belt and measure
the distance it moves. See Figure 28 on page 53.
2. Do one of the following:
• If the drive belt movement measures between
3/8" (10 mm) and 7/16" (12 mm), the drive belt
tension is correct. You do not need to set the drive belt
tension.
• If the drive belt tension is not correct, continue with the
following steps to set the drive belt tension.
3. Loosen (do not remove) the four bolts that attach the
engine mount to the machine frame. See Figure 26 on page
51.
4. Use the drive-belt tensioning bolt to set the drive belt
tension. See Figure 27.
5. Do steps 1, 2, and 4 again, until the drive belt tension is
correct.
6. Tighten the four engine mount bolts.
7. Do step 1 again.
8. Do one of the following:
• If the belt tension is correct, continue with step 9.
• If the belt tension is not correct, do steps 3 through 7
again.
9. Align the drive belt.
For instructions, see Align the Drive Belt.
10. Use a calibrated torque wrench to torque the four engine
mount bolts to 19 lbf•ft (25 N•m).
11. Check the drive belt tension again after 10 hours of
operation.
9.9.3 Align the Drive Belt
A laser alignment tool or 50" (127 cm) straight edge
is necessary for this procedure. A laser alignment
tool is the most accurate.
Check the drive belt alignment after every 8 hours of
operation.
The maximum misalignment is 1/32" (1 mm).
1. Align a laser beam or straight edge (alignment tool) with
the back edge of the rotor sheave and the engine clutch
flywheel. See Figure 29 on page 53.
2. Examine the distance between the drive belt and the
alignment tool, along the length of the drive belt.
3. Do one of the following:
• If the distance between the drive belt and the alignment
tool is the same along the length of the drive belt,
the drive belt is aligned. The following steps are not
necessary.
• If the distance between the drive belt and the alignment
tool are not the same along the length of the drive belt,
continue with the following steps to align the drive belt.
4. Measure the distance between the drive belt and the
alignment tool at the rotor sheave and at the engine clutch.
5. Subtract the low number from the high number.
6. Do one of the following:
• If the calculated number is less than or equal to the
maximum misalignment, the drive belt is aligned.
Do steps 11 and 12 of Replace the Drive Belt on page
51.
• If the calculated number is more than the maximum
misalignment, continue with the following steps to align
the drive belt.
7. Find the cause of the misalignment, and then adjust one of
the following:
• The engine mount.
For instructions, see Align the Engine Mount on page
53.
• The rotor sheave.
For instructions, see Align the Rotor Sheave on page
54.
52
BXT Series
Wood Chipper