Usage:
Challenger 65 &
65B (7YC),
Challenger 65C, 65D (2ZJ),
Challenger 70C (2YL),
Challenger 75 (4CJ),
Challenger 75C (4KK),
Challenger 75D (5AR),
Challenger 85C (9TK),
Challenger 85D (4GR) Agricultural Tractors
- SUPPLEMENT: OCTOBER 12, 1998
Service Magazine SEPD0430, Article 3, Page 2, August 17, 1998; "Belt Selection, Bolt Torque, And Special Application Drive Wheel Scraper Maintenance Recommendations" .
The width of the inside protected belt in the third paragraph under the heading "Choosing the Correct Belt" is incorrect. The correct width for the inside protected belt should read 762 mm (30 inch). The 762 mm (30 inch) inside protected belt is the only belt that is approved for use with the special application drive wheels.
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Reference: Operation and Maintenance Manual, SEBU7072
Special application drive wheels can stop belt to drive wheel slip. In order to get the desired service life from a belt, the special application drive wheel must be matched with a proper type of belt and the drive wheel scraper must be properly adjusted.
NOTE: It is important that machines that are equipped with special application drive wheels are equipped with the correct belt and that the scrapers are properly adjusted.
Choosing The Correct Belt
Flotation is best with wide belts. The penetration (traction) of the grouser is better on narrow belts. (Even with narrow belts, the contact area of a track-type machine is greater than the contact area of comparable wheel type machine.) The balance between slippage and flotation must be considered when you equip a machine with wide belts.
The inside protected belt is the only belts that is recommended for use with special application drive wheels.
Inside protected belts provide protection to the inside diameter of the belt. The inside protected belts are available in the following width: 635 mm (25.0 inch).
Inside protected belts have an additional set of breaker cables (1). Also, there are two additional sheets of rubber between the zero degree cables and the inside surface of the belt. The zero degree cables are parallel to the belt's axis. Breaker cables (2) are aligned at varying degrees to the zero degree cables. These belts are for applications that may result in damage to the rubber on the inside of the belt. Damage may also occur to the zero degree cables. The following types of soil are examples of these applications: rocky soil, sandy soil and muddy soil. Keeping the zero degree cables intact is essential to getting normal life from a belt. Inside protected belts are rquired with special application drive wheels.
Checking The Scrapers For The Special Application Drive Wheel
The belt's life may be shortened by missing scrapers or scrapers that are not properly adjusted. Make sure that the scrapers are in place and that the bolts are tight. Severely worn scrapers should be replaced.
Adjusting The Scrapers For The Special Application Drive Wheel
Adjust scraper (1) to an initial Dimension (A) of 5 ± .5 mm (0.2 ± 0.02 inch). Adjust scraper (2) to an initial Dimension (B) of 2 ± .5 mm (0.08 ± 0.02 inch). Dimension (A) will increase as scraper (1) wears. When Dimension (A) is 9 mm (0.35 inch) readjust the scrapers to 5 ± .5 mm (0.2 ± 0.02 inch).
Scrapers may be inverted in order to provide additional service life. If a scraper is severely worn, the scraper should be replaced.
Scraper (3) is installed in order to provide a clean groove for the guide blocks. Adjust scraper (3) in order to provide a Dimension (C) of 12 ± 3 mm (0.50 ± 0.12 inch). Dimension (C) is between the center of the drive wheel and the end of the scraper. The Dimension (D) between scraper (3) and the edge of the drive wheel should be 8 ± 3 mm (0.30 ± 0.12 inch).
Scrapers that are missing or scrapers that are not adjusted properly can severely shorten the life of the belt. Make sure that the scrapers are adjusted correctly and that the bolts are tight. If a scraper is severely worn, the scraper should be replaced.
Drive Wheel Bolt Torque
When drive wheels are removed, the drive wheel bolts on both sides of the machine should be retightened 10 service hours after the drive wheels are reinstalled. Tighten 12 bolts (1) to a torque of 700 ± 90 N·m (516 ± 66 lb ft). Tighten 18 bolts (2) to a torque of 750 ± 90 N·m (553 ± 66 lb ft).
NOTE: These torques apply to both the standard drive wheel and to the special application drive wheel.