BEARING 8N7933 - Caterpillar

Important! Please Read
When working on or around air brake systems and components, the following precautions should be observed:1. Always block vehicle wheels. Stop engine when working under a vehicle. Depleting vehicle air system pressure may cause vehicle to roll. Keep hands away from chamber push rods and slack adjusters; they may apply as system pressure drops.2. Never connect or disconnect a hose or line containing air pressure. It may whip as air escapes. Never remove a component or pipe plug unless you are certain all system pressure has been depleted.3. Never exceed recommended air pressure and always wear safety glasses when working with air pressure. Never look into air jets or direct them at anyone.4. Never attempt to disassemble a component until you have read and understand recommended procedures. Some components contain powerful springs and injury can result if not properly disassembled. Use only proper tools and observe all precautions pertaining to use of those tools.Description
The function of the air compressor is to provide and maintain air under pressure to operate devices in the air brake and/or auxiliary air systems.The Tu-Flo 700 is a two cylinder single stage, reciprocating compressor with a rated displacement of 15.5 cubic feet of air per minute at 1250 rpm.The compressor assembly is comprised of three cast iron major sub-assemblies; the cylinder head, the cylinder block and the crankcase.The cylinder head houses the discharge valving and is installed to the cylinder block. The cylinder block houses the cylinder bores and inlet valves and is installed to the crankcase. The crankcase houses the crankshaft and main bearings.The Tu-Flo 700 compressor is available in various mounting and drive configurations as required by engine designs. Two (2) convenient governor mounting pads are provided on the block.The cylinder head and block are cooled by coolant routed to the compressor from the engine cooling system.Lubrication for the internal parts of the Tu-Flo 700 compressor is provided by the engine's pressurized oil system.A nameplate, identifying the compressor piece number and serial number, is attached to the side of the crankcase. A nameplate with a black background denotes a new compressor and a red background designates a factory remanufactured unit.Operation
The compressor is driven by the vehicle engine and is operating continuously while the engine is running. Actual compression of air is controlled by the compressor unloading mechanism and the governor. The governor is generally mounted on the compressor and maintains the brake system air pressure to a preset maximum and minimum pressure level.Intake And Compression Of Air (Loaded)
Figure 1During the down stroke of the piston, a slight vacuum is created between the top of the piston and the head, causing the inlet valve to move up and off its seat. (Note: The discharge valve remains on its seat.) Atmospheric air is drawn through the air strainer by the open inlet valve and into the cylinder (see Fig. 1). As the piston begins its upward stroke, the air that was drawn into the cylinder on the down stroke is being compressed.