Disassembly and Maintenance of The Diesel Generator Fuel Pump Part 2

Following the last article, after the Cummins diesel generator oil pump is reassembled, it is required that the moving parts such as the piston and the ejector rod of the oil pump should move well throughout the stroke, and no blockage or jamming is allowed. The pressing hand pump should be light and flexible. When installing the check valve spring, it is important to note that the check valve spring must be accurately embedded in the spring matching groove.

Test of the oil transfer pump: After the oil transfer pump is reassembled, the performance test shall be carried out. The working performance indicators of the oil transfer pump are mainly the oil supply pressure and oil supply amount. The oil supply pressure is generally 49-196kPa, and the working performance can be measured on a special test bench.

Tightness test: The oil transfer pump can also be tested on the special test bench. When the oil supply pressure is 98KPa and the working speed is 50r/min, there shall be no oil leakage within 1 minute at the joint between the push rod and the pump body. Tighten the handle of the hand oil pump and block the oil outlet, immerse the oil transfer pump in clean kerosene or diesel oil, pass the compressed air of 147-196kPa through the oil inlet, and check the air leakage between the pump body and the push rod, collect bubbles with a measuring cylinder. If the collected volume in 1 minute is within 50ml, and the diameter of the bubbles does not exceed 1mm, it means that the gap is normal and well sealed, otherwise it should be repaired or replaced.

Test the oil supply pressure and oil supply volume of the oil transfer pump: install the Cummins diesel generator oil transfer pump on the test bench. When the rotation speed is 600r/nfin, the oil delivery pressure should not be lower than 147kPa, and when the rotation speed is 750r/min, the oil delivery pressure should be When the 206kPa oil pump should be continuously supplied with oil, the oil volume should not be less than 250ml/min.

Oil suction capacity test: Install the fuel pump on the fuel injection pump, connect a rubber hose with a diameter of 8-10mm and a length of 2m to the oil inlet of the fuel pump, and test the oil suction capacity of the fuel pump from a fuel tank below 1m. When the speed of the fuel injection pump is 200r/min, the fuel delivery pump should suck out the oil within 18s to be qualified; if the fuel injection pump rotates for more than 36s and the fuel delivery pump has not supplied oil, it means that it needs to be repaired.

Hand oil pump performance test: Drain the diesel oil in the oil inlet pipe, and then reciprocate the hand oil pump handle at a speed of 2-3 times/rain, and record the diesel oil from the fuel tank where the liquid level is not less than 1m below the oil inlet of the oil transfer pump. The time to the oil outlet should be no more than 1min, otherwise it should be overhauled. The test should be carried out under the condition that the pipeline is well sealed, and the hand oil pump is working: the oil discharged during operation should not have foam.

Starlight Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to sales@dieselgeneratortech.com we will pay highly attention on your question.