Bandit 490 - Belt Tension

Bandit
Copyright 11/10 PAGE 30
MODEL 490 MAINTENANCE SECTION
BELT TENSION
GENERAL RULES FOR TENSIONING
1. Check tensioning during the rst 2 through 48 hours of run-in operation especially.
2. Over tensioning or under tensioning shortens belt and bearing life.
3. Keep belts free from foreign materials that may cause the belt to slip.
4. Make V-drive inspection on a periodic basis. Never use belt dressing as this will damage
the belt and cause early failure.
5. Belts should never be forced over the sheave. Allow enough room for belts to slip on.
6. Always make sure sheaves are aligned properly.
TENSIONING PROCEDURE
Main Drive Belts
Follow all pre-maintenance shut down procedures. Locate the center of the belt span between the sheaves.
Push or pull on the belt until the belt has deected 1/4” (6.4 mm). Record the push or pull force. The force should
be 8 to 9 lbs./belt (3.6 to 4.1 kg/belt) for an engine powered machine or 7 to 8 lbs./belt (3.2 to 3.6 kg/belt) for a
PTO machine. Adjust the belt tension if the force falls outside of this range. If belts are not properly adjusted
belts will slip, glaze over, and be ruined. This is NOT covered by warranty.
1) Remove beltshield.
2) To adjust the belt tension, loosen the four engine mounting bolts and the jam nuts on the engine adjuster
on the fan or front side of the engine.
3) Adjust the belt tension with the engine adjuster on the crank shaft end of the engine. If you have to push
the engine with the adjuster, the belts will tighten slightly after the engine is realigned.
4) Use the engine adjuster on the fan or front side of the engine to realign the engine, so the engine
sheave and chipper sheave are aligned. The sheaves can be checked with a string or straight edge.
5) Torque the two engine mounting bolts (see Torque Chart for the correct torque) on the opposite side of
the engine from the engine adjusters.
6) Loosen the jam nuts on the engine adjuster on the fan or front side of the engine.
7) Torque the engine mount bolt and then tighten the engine adjuster jam nuts on the fan or front side .
8) Hand tighten the remaining engine mount bolt and loosen the engine adjuster jam nut on the crank shaft
end half a rotation. Loosen the engine adjuster jam nuts all the way and torque the engine mount bolt.
9) Tighten the engine adjuster jam nuts on the crank shaft end.
10) Recheck the belt tension and alignment, if readjustment is needed go back to step 2.
11) Reinstall beltshield.
DO NOT IGNORE THIS MAINTENANCE RULE!
New belts stretch very soon and must be adjusted several times in the rst few hours of operation. Adjust after
one hour of operation, then every four hours until the belts quit stretching.
Failure to do this will cause the belts to burn and y off. THIS FAILURE IS NOT COVERED BY WARRANTY!
NOTICE It is a good practice to rotate the belts during tensioning. Then recheck deections. The belts may
need to be tightened again.
NOTICE lbs./belt (kg/belt) is per 1 belt. If equipped with 4 groove poly band belt, lbs./belt (kg/belt) must be multiplied
by 4. If equipped with two 3 groove poly band belts, lbs./belt (kg/belt) must be multiplied by 3 for each poly band
belt.