BEARING-SLEEVE 4K1102 - Caterpillar

The most likely causes for faulty fuel injection performance are: 1. Air in the fuel system.2. Low fuel supply.3. Water in the fuel.4. Clogged fuel filters.5. Insufficient fuel transfer pump pressure.If these conditions are checked and corrected and the engine still does not perform properly, the fuel injection equipment should be checked.Checking Fuel Injection Equipment
Before removing a fuel injection pump or valve for testing from an engine that is missing or puffing black smoke at the exhaust, a simple check can be made to determine which cylinder is causing the difficulty. With the engine running at a speed which makes the defect most pronounced, momentarily loosen the fuel line nut on the injection pump sufficiently to cut out the cylinder. Check each cylinder in the same manner. If one is found where loosening makes no difference in the irregular operation of the engine or causes puffing of black smoke at exhaust to cease, probably the pump and valve, for only that cylinder, need be tested.Fuel Injection Valve
The function of the fuel injection valve is to inject and atomize the fuel from the fuel injection pumps into the precombustion chambers. Irregular engine operation and smoking may be caused by an improperly operating injection valve.The fuel injection valve is installed in the precombustion chamber.The fuel injection valve assembly consists of the body (3), nut (2), and the capsule-type nozzle assembly (4).Only the nozzle assembly need be replaced.The nozzle assembly (4) and body (3) are held in place by the nut (2), and they can be removed by disconnecting the fuel line assembly (1) and removing the nut and seal.The body and the nozzle assembly can then be lifted out. The nozzle assembly is only finger-tight on the body.When installing a fuel injection valve, always check the seats of both the nozzle and the precombustion chamber.
FUEL INJECTION VALVE CROSS-SECTION
1-Fuel line assembly. 2-Nut. 3-Body. 4-Nozzle assembly.Tighten the nut (2) to the torque of 100-110 lb. ft. (13,8-15,2 mkg). Excessive tightness will damage the nozzle. Excessive looseness will allow the nozzle to leak and in some instances cause the nozzle case to bulge or split.Checking Fuel Injection Valves
The condition of a capsule type nozzle assembly can be tested out of the engine on the Caterpillar Diesel Fuel Injection Test Apparatus. The spray characteristic, valve unseating pressure, and the rate of leakage of the nozzle assembly can be determined.Fuel Injection Pumps
Air in the fuel system is bled through the bleeder manifold (5) when the bleeder valve is opened and fuel enters the bleeder manifold through passage (7). The injection pump plungers (3) and the lifters (8) are lifted by cams on the camshaft (9) and always make a full stroke. Each pump (1) measures the amount of fuel to be injected into its respective cylinder and delivers it to the fuel injection valve. The amount of fuel pumped per stroke can be varied by turning the plunger in the barrel. The plunger is turned by the governor action through the rack (6) which meshes