300kw Cummins Generator PT Pump Diesel Engine Speed Adjustment

Due to the fact that the fuel pump in the PT fuel system of the 300kw Cummins generator only outputs low-pressure oil without high-pressure fuel pipes, there is no pressure wave problem at high speeds, and the fuel injector plunger has a fast downward speed and a small spray hole size, the maximum fuel injection pressure can reach 100MPa, which is conducive to fuel atomization, sufficient combustion, pollution discharge, and good economy. Diesel engine shutdown is achieved by using a fuel cut-off valve to close the oil circuit and shut down the engine.

The on-site adjustment of the PT fuel pump for the 300kw Cummins generator diesel engine depends on the diesel engine status, equipment load, and the accuracy of the instruments used. The inspection and adjustment methods for different operating conditions are as follows:

1. Idle speed: With the Cummins generator running, remove all air from the oil circuit and bring the diesel engine to operating temperature; Unscrew the screw plug from the cover of the PT-G two-stage governor spring assembly; Adjust the idle speed, screw in the adjustment screw to increase the idle speed, and screw out the adjustment screw to decrease the idle speed; After adjusting the idle speed, reinstall the plug.

On the PT fuel pump equipped with MVS full speed governor, the maximum speed and idle adjustment screws are located on the governor cover. After adjustment, immediately tighten the locking nut to prevent air from entering the fuel pump.

For various series of diesel engines, the factory has recommended idle speed, which allows for reasonable variation. If it is too high, it is difficult to shift gears, and if it is too low, it is easy to stall.

If the idle speed is unstable, it is related to the governor plunger, and the extension of the flying hammer booster plunger should be checked.

2. Maximum speed (accelerator pedal pressed to the bottom): The maximum speed is usually calibrated on the PT fuel pump test bench, usually by adding or reducing the high-speed spring gasket of the governor; If it has been adjusted on the test bench, there is no need to make any further changes.

The on-site inspection method for the highest no-load speed: Place the transmission in neutral or the clutch in the disengaged state, open the throttle valve and maintain the fully open position. At this time, the maximum speed of the diesel generator should be 10% -12% higher than the speed at the disconnection point of the governor; When this speed greatly exceeds the specified value, the governor component should be inspected for faults or its parts should be checked for suitability.

3. Governor disconnection point speed: When the throttle valve is fully open, increase the load until the speed drops to at least 100r/min lower than the rated speed, then gradually reduce the load, while observing the fuel outlet pressure gauge (as the load decreases, the fuel outlet pressure will increase until the governor starts limiting fuel supply, and then as the load decreases, the fuel outlet pressure will start to decrease), which is the governor disconnection point, If this speed is lower than the rated speed of the diesel generator, it will not have a limiting effect (for example, if the diesel engine speed is 2100r/min, the speed at the disconnection point of the governor is 2120-2140r/min). If the speed at the disconnection point of the governor is higher or lower than the specified value, the adjustment can be made by reducing or adding shims from behind the high-speed spring of the governor until the speed at the disconnection point of the governor meets the specified value when checked again.

Dingbo 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.