OM4206 06/06 Maintenance - Section 42 Automatic Lubrication System Page 42-1 AUTOMATIC LUBRICATION SYSTEM GENERAL DESCRIPTION During the down stroke, the pump cylinder is extended into the grease. Through the combination of shovel action and vacuum generated in the pump cyl- inder, the grease is forced into the pump cylinder. Simultaneously, grease is discharged through outlet (9) of the pump. The volume of grease during intake is twice the amount of grease output during one cycle. During the upstroke, the inlet check valve closes, and one-half of the grease taken in during the previous stroke is transferred through the outlet check and discharged to the outlet port.
The automatic lubrication system is a pressurized lubricant delivery system which delivers a controlled amount of lubricant to designated lubrication points. The system is controlled by an electric timer which signals a solenoid valve to operate a hydraulic motor powered grease pump. Hydraulic oil for pump opera- tion is supplied by the truck steering circuit. Grease output is proportional to the hydraulic motor input flow. A pump control manifold (4, Figure 42-1), mounted on top of hydraulic motor (2), controls input flow and pressure. 24VDC solenoid (5) mounted on the manifold turns the pump on and off. NOTE: Newer models are equipped with fixed hydraulic motor controls.
Over-pressurizing of the system, modifying parts, using incompatible chemicals and fluids, or using worn or damaged parts, may result in equipment damage and/or serious personal injury. The pump is driven by the rotary motion of the hydraulic motor, which is then converted to recipro- cating motion through an eccentric crank mechanism. The reciprocating action causes the pump cylinder to move up and down. The pump is a positive displace- ment, double-acting type as grease output occurs on both the up and the down stroke. DO NOT exceed the stated maximum working pressure of the pump, or of the lowest rated component in the system.
DO NOT alter or modify any part of this system unless approved by factory authorization. DO NOT attempt to repair or disassemble the equipment while the system is pressurized. Ensure all fluid connections are securely tightened before using this equipment. Read and follow the fluid manufacturer's recommendations regarding fluid compatibility, and the use of protective clothing and equipment. Check all equipment regularly and repair, or replace, worn or damaged parts immediately. This equipment generates very high grease pres- sure.
Extreme caution must be used when operat- ing this equipment, as material leaks from loose or ruptured components can inject fluid through the skin and into the body, causing serious bodily injury, including possible need for amputation. Adequate protection is recommended to prevent splashing of material onto the skin or into the eyes. 1. Orifice Fitting 2. Hydraulic Motor 3. Pressure Reducing Valve 4. Pump Control Manifold FIGURE 42-1. PUMP COMPONENTS 5. Solenoid Valve 6. Pressure Gauge 7. Pump Assembly 8. Flow Control Valve 9. Grease Outlet 10. Grease Pickup Tube 11. Manual Override If any fluid appears to penetrate the skin, get emergency medical care immediately!
DO NOT treat as a simple cut. Tell attending physician exactly what fluid was injected.