BREATHER 0980255 - Caterpillar

Air Compressor Governor (Midland) (1) Adjusting screw.(2) Exhaust hole.To increase the system air pressure, turn adjusting screw (1) in a clockwise direction. Turn the adjusting screw counterclockwise to decrease the air system pressure.The correct cut-out pressure is 795 to 880 kPa (115 to 128 psi). The cut-in pressure is approximately 170 kPa (25 psi) less than the cut-out pressure.3. Governor Adjustment (Bendix)
Air Compressor Governor (Bendix)(1) Adjusting screw.To increase the system air pressure, turn adjusting screw (1) counterclockwise. Turn the adjusting screw clockwise to decrease the air pressure.The correct governor cut-out pressure is 795 to 860 kPa (115 to 125 psi). The cut-in setting is 660 to 690 kPa (95 to 100 psi).4. Governor Parts Put soap suds (water with plenty of soap) around the governor gaskets and exhaust hole (2) of the Midland governor. Bubbles must be seen from the exhaust hole only when the governor parts move to air pressure cut-in, any other bubbles show the governor needs a repair. The bubbles do not show a broken or weak spring. Refer to "Disassembly And Assembly, Air Compressor Governor".5. Outlet Valve The outlet valves are in the cylinder head. It is necessary to remove the cylinder head from the air compressor before the outlet valves can be removed, cleaned or replaced. Refer to "Disassembly And Assembly, Cylinder Head".6. Inlet Valve The inlet valves are in the cylinder head. It is necessary to remove the cylinder head from the air compressor before the inlet valves can be removed, cleaned or replaced.7. Piston Rings. Cylinder Block, Pistons The air compressor is removed from the engine to remove the pistons, rings and cylinder block. Refer to "Disassembly And Assembly, Pistons And Rods".8. Unloader Valves
Air Compressor Unloader Valves(3) Cover.(4) Gasket.(5) V-seal.(6) Unloader valve.(7) Spring.Remove cover (3), on top of the cylinder head, over the unloader valves. Check the condition of each spring (7) and unloader valve (6). Replace, if necessary. Install new V-seals (5) and put plenty of 4L-7464 Grease-Silicone on the seals. Install the springs, the unloader valve (with a new V-seal), new gasket (4) and cover (3). Torque for the two small bolts is 9 to 12 N m (75 to 105 lb in). Torque for the remaining long bolt is 38 to 44 N m (27 to 33 lb ft). Refer to "Assemble Cylinder Head".9. Line From Supply Tank The line from the air supply tank to the inlet and filter of the air compressor governor must not have a break or a bend that would make the passage in the line too small. Install a new line, if necessary.10. Leaks in the Air System Check the complete air system and the air components for air leaks. When an air line connection is tightened, put soap suds (water with plenty of soap) on the connection to see if the compressed air makes bubbles in the soap suds (a leak).11. Crankshaft, Crankcase and Bearings The air compressor is removed from the engine to remove the crankshaft and bearings from the