Altec DRM 12, Manual

Page: 53 / 143

48 • Section 7 — Maintenance
Make sure that the drum and drive system have come
to a complete stop before attempting any maintenance
in this area.
Inspect belt/pulley condition according to Figure 7.2.
Replace as necessary.
Figure 7.2 — Belt Wear
1. Remove belt guard.
2. Visually inspect drive belt for cracks or fraying. Vi -
sually inspect sheaves for signs of wear, cracks, or
loose bushings.
3. Inspect belt tension. At the center point between the
sheaves, the belt should deflect
3
/
8
” with 8 pounds of
pull. Under-tensioning can cause unnecessary belt
wear.
4. Overtensioning can cause premature PTO and/or
bearing failure.
5. Check drum cutter head/engine alignment by placing
a non-flexible straight edge against the outside sur -
face of the drum cutter head sheave and the engine
sheave. Alignment is correct when both inner and
outer surfaces of both sheaves are in contact with
the straight edge (refer to Figure 7.3).
Figure 7.3 — Sheave Alignment
No gaps between straight edge and sheave on both
sheaves.
Belt Adjustment
1. Back-off the engine mounting adjusting screws.
2. Loosen all of the engine mounting bolts.
3. Tighten or loosen the adjusting screws, as appropri-
ate, while monitoring the sheave alignment and belt
tension.
4. When the proper sheave alignment and belt tension
have been achieved, retighten the engine mounting
bolts.
5. Retighten the adjusting screw locking nuts.
6. Reinstall the belt guard and tighten all fasteners
securely.
Warning
Death or serious injury may result if maintenance
procedures are not completed.
Make sure that all tools and hardware are removed from
the head and discharge chutes or any other area where
maintenance, inspection or service was performed.
Make sure that all fasteners and adjustments are secured
properly before starting the unit.
Worn Sheave
Belts
Worn Belt
Good Belt
Belts
Belts
Space
Reduced
Space
Straight Edge
No Gaps