VALVE-VELOCITY 9U7464 - Caterpillar

You must read and understand the warnings and instructions contained in the Safety section of this manual before performing any operation or maintenance procedures.Hydraulic Oil System
Check Oil Level
If leaks are found in the hydraulic system, check the hydraulic oil level and repair leaks if necessary. Refer to the machine manufacturer's literature for location and method of checking hydraulic oil level.Midrollers
Check Oil Level
1. Position the midroller with the level/fill plug on the center line of the midroller.2. Remove the level/fill plug. Maintain the oil level to the bottom of the level/fill plug hole. Add oil if necessary.3. Clean and install the level/fill plug.4. Repeat procedure for the other midrollers.Drive Belt
Inspect
1. Inspect the belt for cuts or gouges.2. If cuts or gouges are found, examine to determine if the cables in the belt are exposed. When any of the cables are exposed to moisture, they deteriorate by rusting. The rubber belt has four layers of cable inside, similar to the cables used in radial tires. The inter cable, called the zero degree (0°) cable, is the most important cable. The zero degree (0°) cable is located about 8 mm (.31 in) beneath the inside surface of the belt and controls belt tension. The three other cables are called breaker cables and provide lateral support to the belt. The breaker cables are located between the outer surface of the belt and the zero degree (0°) cable and are of less importances than the zero degree (0°) cable.It is important to make repairs whenever the zero degree (0°) cables are exposed or damaged.However, when breaker cables are exposed or damage, repair is not critical. Breaker cables need to be repaired only if they become exposed over a large area or if individual cables extend outside the belt surface.3. To determine if the zero degree (0°) cables need repair, inspect for cuts or gouges that may be deep enough to contact the cables. Use a blunt tool like a flat head screwdriver to feel for cables at the bottom of cut or gouges. Do not use a sharp tool which could deepen the cut.Small cracks may develop between the base of the guideblocks and the belt. These cracks relieve stresses induced during the curing process and are not expected to extend inward more than 13 mm (.51 in).Cuts, gouges and wear on the guideblocks are not expected to cause operational problems.Portions of individual grouser bars that become separated from the belt are not expected to affect traction and need not be replaced.Pieces of rubber may become separated from the midroller rim due to rocks and debris that gets in the undercarriage system. If more than 50 percent of the rubber is missing from any midroller, the midroller should be replaced. Pieces of rubber may become separated from the drive or idler wheel rims due to rock and debris in the undercarriage system. If missing rubber causes slippage between the wheel and the belt, the wheel must be replaced. Consult your Caterpillar dealer