PRESS PISTON 5P3569 - Caterpillar

General
There are three methods of providing clean air to the BX-2150: 1. Naturally aspirated - Compressor utilizes its own attached air strainer (polyurethane sponge or pleated paper dry element).2. Naturally aspirated - Compressor inlet is connected to the engine air cleaner or the vacuum side (engine air cleaner) of the supercharger or turbocharger.3. Pressurized induction - Compressor inlet is connected to the pressure side of the supercharger or turbocharger.See the Tabulated Technical Data section of this manual for specific requirements for numbers 2 and 3 above.
Fig. 8 Inlet Check ValveInlet Check Valve
An inlet check valve is used on some naturally aspirated BX-2150 Air Compressors (never with pressurized induction, see number 3 above) to prevent inlet oil misting during the unloaded cycle. The inlet check valve is mounted directly at the inlet cavity of the compressor. It consists of three parts, the inlet gasket, the inlet check valve reed, and the inlet check valve seat (see Fig. 8). During the compression cycle, the inlet check valve reed is drawn away from its seat uncovering three inlet holes which allows air to flow into the compressor inlet cavity. A machined stop in the cylinder head inlet cavity limits the travel of the inlet check valve reed. In the unloaded cycle the inlet check valve reed rests on its seat covering the three inlet holes. Air from within the compressor is prevented from exiting the inlet cavity.The inlet check valve may only be used in conjunction with cylinder heads incorporating the machined inlet check valve stop in the inlet cavity. An inlet gasket is required since its thickness contributes to the minimum reed travel required. Either side of the inlet check valve reed may be installed next to the gasket; however, the free end (tip) of the inlet check valve reed must coincide with the machined inlet cavity stop in the cylinder head. The inlet check valve seat must be installed, so that the two half moon indentations are on the side facing the inlet check valve as illustrated in Figure 8.