BRACKET ASSEM. 1252974 - Caterpillar

Do not run the engine under load for more than 5 minutes with return line blocked.
D. Damaged Fuel Transfer Pump Parts- ... Check bypass valve to see if dirt or other debris could make the valve stick. Clean or replace valve if damaged. If bypass valve is good, remove and disassemble fuel transfer pump to check for wear in the gears.9. A very small amount of air in the fuel may not affect the transfer pump fuel pressure, but could affect the performance at the nozzles. The 2P8278 Flow Tube can be installed ahead of the fuel transfer pump. This will allow a visual check of any air in the fuel when the engine is running. Another method to check for air in the fuel is to put the fuel tank end of the fuel return line in a container of fuel.10. Install the 5P2150 Horsepower Meter according to Special Instruction SEHS7050. The specified fuel rate at full load is given in the RACK SETTING INFORMATION. Do the wheel horsepower test again as shown in Procedure No. 2, but this time record the fuel rate and rpm. This fuel system has a constant flow of fuel that is returned to the fuel tank. This orifice must be blocked before accurate fuel rate readings can be taken. Do not run the engine under load for more than 5 minutes with return line blocked.11. If the fuel rate was too low, install 5P4203 Field Service Tool Group and check the fuel system setting. The correct fuel system setting is given in RACK SETTING INFORMATION. If fuel system setting is not correct, the adjustment procedure is shown in Testing and Adjusting section of this Service Manual under subject FUEL SYSTEM SETTING. If the fuel rate was low, and the fuel system setting is correct, check the items that follow in the sequence shown:A. Remove nozzles and check to see if they are the correct nozzles for your engine or if they have been wire brushed. Either condition will affect performance.B. Check for any restrictions to fuel flow in lines between fuel filter and nozzles. Any sharp bend in the lines could cause a restriction of fuel delivery.C. Check governor for worn servo parts (valve, piston, cylinder or sleeve). A worn bushing or worn spring seat can change governor operation. Also check to see if the correct governor spring is installed.12. Check the timing of the fuel injection pump camshaft to the engine flywheel by use of 4N6430 Timing Pin. If timing pin does not go into camshaft notch when flywheel timing bolt is installed, see Fuel System of the Testing and Adjusting section of this Service Manual for the subject FUEL SYSTEM ADJUSTMENTS.13. Install the 2P8280 or 1P3500 Injection Timing Group to check the automatic timing advance unit. Do not do this test with Chassis Dynamometer load on the engine. The transducers are designed for engine no-load conditions.Check to see if advance is smooth and constant through the proper speed range.