Belt
Reference: See the following publication for detailed information about the usage and selection of belts: Special Instruction, REHS0576, "Selection and usage of Mobil-Trac Belts".
Standard Belts
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| Illustration 1 | g00494510 |
Undercarriage (1) Rear drive wheels (2) Hardbar (3) Belt tensioner (4) Front idler (5) Midwheels (6) Mounting holes (7) Guide blocks (8) Reaction arm (9) Belt | |
Belt (9) is made of a flexible rubber. Also, the belt has rubber grousers.
There are 72 grousers on a standard belt. The height of the grousers are 63.5 mm (2.5 inch). The grousers are arranged in a chevron pattern at 30 degree angles.
A standard belt has 36 guide blocks (7) on the center of the inside of the belt. The guide blocks are used in order to keep the belt around drive wheels (1) and front idlers (4) .
Note: Replace belt (9) when the height of the grousers is less than 12.7 mm (0.5 inch) and belt slippage commonly exceeds ten percent.
Belt (9) is available in the following widths: 406 mm (16 inch), 457 mm (18 inch), 508 mm (20 inch), 635 mm (25 inch) and 813 mm (32 inch).
Special Application Belts
Special application belts have shorter grousers than standard belts. The height of the grousers are 38 mm (1.5 inch). The grousers are arranged in a chevron pattern at 30 degree angles. There are 96 grousers on a special application belt. Also, the grousers on special application belts are wider than standard belts.
A special application belt has 36 guide blocks (7) on the center of the inside of the belt. The guide blocks are used in order to keep the belt around drive wheels (1) and front idlers (4) .
Use the special application belts when the standard belt is not suitable for the application. For example, use the special application belts on firm, packed soil and on other hard surfaces. Also, these belts can be used in order to minimize the amount of soil that is disturbed when you turn during cultivating.
Special application belts can be used for primary tillage or for secondary tillage. However, the maximum drawbar pull for a machine that is equipped with special application belts may be as much as 20 percent less than the maximum drawbar pull for a machine that is equipped with standard belts.
In wet conditions, the special application belts do not have a good self-cleaning feature. Any belt that is packed with material between the grousers will experience reduced traction.
Special application belts are available in the following widths: 457 mm (18 inch) and 635 mm (25 inch).
Extreme Service Belts
Extreme service belts are designed for high drawbar loads and extremely abrasive conditions. Extreme service belts have additional protection on the inside diameter of the belt. In addition, the belts have 96 grousers instead of 72. The grousers are as wide as the grousers on the special application belts. Also, the grousers are as tall as the grousers on the standard belts. The belt has more total area of grousers than the standard belts. This provides a smoother ride when the machine is used in the same application as the standard belt.
Side Slope Belts
Side slope belts are used for applications that involve a substantial amount of work on inclines, on slants and on downward slopes. Working on inclines can apply more load on the uphill side of the guideblock. As a result, some applications on side slopes can cause the guideblocks to wear faster than the grousers.
In some cases, the wear of the guide block will determine the life of the belt. For these applications, side slope belts with 48 guide blocks are available. All other types of belts have 36 guide blocks. The additional guide blocks give lower individual loading to each guide block when the machine is running on slopes. Side slope belts have standard grousers. The belts have the extra protection on the inside diameter.
Note: The side slope belts must be used with the drive wheels that have the 60 degree chevron pattern. The drive wheels with the 60 degree chevron pattern have an improved profile that distributes the side load more uniformly to the guideblocks.
Track Gauge
Reference: See the following publications for detailed information about changing the gauge: Special Instruction, SEHS9982, "Procedure to Change Track Gauge" and Video Tape, SEVN3762, "Procedure to Change Track Gauge".
Use spacers to adjust the gauge in increments of 50.8 mm (2 inch). The spacers are mounted to both the flanged rear axle and the hardbar on each side of the machine.
Reference: For more information on available spacers, see Special Publication, SENR8458, "Gauge and Spacer Combination Charts".
Note: Some combinations of belts and spacers can not be used together.
Machine With a 1524 mm (60 inch) Gauge
The gauge can be increased to a gauge of 2286 mm (90 inch).
Note: A minimum of 1067 mm (42 inch) must be maintained between the inside edges of the two belts.
Machine With a 2032 mm (80 inch) Gauge
The gauge can be increased to 3048 mm (120 inch). Also, a single pair of 508 mm (20 inch) spacers can increase the gauge to 3048 mm (120 inch).
Drive Wheels
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| Illustration 2 | g00494510 |
Undercarriage (1) Rear drive wheels (2) Hardbar (3) Belt tensioner (4) Front idler (5) Midwheels (6) Mounting holes (7) Guide blocks (8) Reaction arm (9) Belt | |
Rear drive wheels (1) are one piece. Rear drive wheels (1) are mounted between the flanged rear axle and reaction arm (8) .
Rear drive wheels (1) are bolted to the rear axle. A duo-cone seal kit is between reaction arms (8) and rear drive wheels (1) .
Reaction arm (8) is bolted to the roller frame. The stationary reaction arm (8) does not pivot at the roller frame. Front idlers (4) pivot at the roller frame.
Rear drive wheels (1) are 1473 mm (58 inch) in diameter. 50.8 mm (2 inch) of rubber is bonded to the rear drive wheels.
A short diamond pattern with wide grooves is molded into the rear drive wheels. The wide grooves allow rear drive wheels (1) to be self-cleaning.
The short diamond pattern keeps the inside of belt (9) clean. This maintains excellent traction between belt (9) and rear drive wheels (1).
Midwheels
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| Illustration 3 | g00494510 |
Undercarriage (1) Rear drive wheels (2) Hardbar (3) Belt tensioner (4) Front idler (5) Midwheels (6) Mounting holes (7) Guide blocks (8) Reaction arm (9) Belt | |
Midwheels (5) are mounted to the roller frame.
Each roller frame has three pairs of midwheels (5). Midwheels (5) evenly distribute the weight of the machine over the length of belt (9) .
Midwheels (5) are 356 mm (14 inch) in diameter. 25 mm (1 inch) of rubber is bonded to midwheels (5). The thick molded rubber helps absorb some of the vibration and shock load from uneven terrain.
The axles for the midwheels are rigidly mounted to the roller frame. The axles are located by a center dowel and secured with a cap and four bolts.
The midwheels use duo-cone seal kits. The midwheels do not need to be removed when a belt is changed.
Front Idlers
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| Illustration 4 | g00494643 |
Roller frame (4) Front idler (10) Swing link (11) Roller frame | |
Front idlers (4) are mounted to swing link (10). Swing link (10) is connected to roller frame (11) .
The connection at roller frame (11) allows front idler (4) to be adjusted. Two bolts that are on roller frame (11) allow front idlers (4) to be pivoted. Front idlers (4) will pivot both left and right in order to align the belts. Proper alignment of the belt can be achieved while the belt is tensioned.
Front idlers (4) are two-piece. Front idlers (4) are 813 mm (32 inch) in diameter. 50.8 mm (2 inch) of rubber is bonded to front idlers (4). The rubber is molded in a straight cut pattern.
Front idlers (4) are not level with the midwheels when the belt is fully tensioned. Front idlers (4) are slightly above the midwheels.
The small difference in height lessens the force when the grousers come in contact with hard surfaces. For example, the small difference in height increases the life of the belt while the machine is roaded.
Hardbar
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| Illustration 5 | g00494510 |
Undercarriage (1) Rear drive wheels (2) Hardbar (3) Belt tensioner (4) Front idler (5) Midwheels (6) Mounting holes (7) Guide blocks (8) Reaction arm (9) Belt | |
Hardbar (2) connects the front of the undercarriage to the machine. The position of hardbar (2) evenly distributes the weight of the machine over the length of the belt.
Hardbar (2) is bolted to a bracket that is bolted to both the extension housing and the transmission.
The connection of the bracket to hardbar (2) is cushioned by an elastomeric bearing. The elastomeric bearing helps isolate the machine from shock loads.