Why does the diesel generator set stall suddenly?

1. When automatic shutdown occurs, the rotational speed drops gradually, and there are no abnormal sounds from the running diesel generator or abnormal exhaust smoke color. The main causes are as follows: the diesel fuel in the fuel tank is exhausted, or the fuel tank valve is closed; the fuel tank vent hole, fuel filter or fuel transfer pump is clogged; or air enters the unsealed fuel line to form an "air lock" (accompanied by unstable rotational speed before shutdown). At this time, the low-pressure fuel line needs to be inspected. First, check the fuel tank, filter, fuel tank valve and fuel transfer pump for blockages, fuel shortage or unopened valves. Then loosen the air vent screw on the fuel injection pump and press the fuel pump button to observe the oil outflow at the air vent screw. If no oil flows out, the fuel line is clogged. If bubbles are present in the outflowing oil, air has entered the fuel line, and sectional inspection and troubleshooting shall be carried out segment by segment. Our optimized fuel supply system solves this risk fundamentally: we equip all generator sets with double-stage high-precision fuel filters, automatic exhaust valves on fuel pipelines and sealed integrated fuel delivery pipelines. The intelligent fuel monitoring module real-time tracks fuel volume, pipeline pressure and air content, and sends early warning reminders before air lock or blockage occurs, completely cutting off this type of shutdown failure.

2. The operation becomes continuously unstable accompanied by abnormal knocking noises when the engine stalls automatically. The main causes include broken piston pins, fractured crankshafts, broken or loose connecting rod bolts, lost valve circlips and valve collets, as well as fractured valve stems or valve springs that lead to valve falling off. Once such conditions are detected during the operation of a diesel generator, shut down the unit immediately for inspection to avoid severe mechanical failures, and send it to a professional maintenance shop for a comprehensive examination. Our core engine adopts high-strength forged alloy crankshaft, wear-resistant reinforced piston pins and anti-loose locking connecting rod fasteners. All moving mechanical parts pass 500-hour continuous overload durability testing before delivery. The built-in vibration and noise sensor system monitors mechanical abnormal knocking in real time, implementing power reduction protection in advance to prevent sudden shutdown caused by mechanical damage, greatly extending the service life of core moving parts.

3. When the diesel generator stalls automatically, its rotational speed drops gradually, the operation becomes unstable, and white smoke comes out of the exhaust pipe. The main causes include water mixed in diesel fuel, damaged cylinder gaskets, or broken automatic decompression devices, etc. It is necessary to replace the cylinder gasket and adjust the decompression mechanism. Our units are equipped with high-efficiency fuel water separation filters to completely isolate moisture in fuel. The cylinder gasket uses high-temperature resistant composite sealing material with anti-corrosion and anti-leakage treatment, and the integrated automatic decompression structure eliminates the risk of component fracture. The exhaust gas online detection function will remind users of water mixing or sealing failure at the early stage of abnormality, avoiding white smoke and unexpected shutdown.

4. There were no abnormalities before the automatic shutdown, and the unit just stalled suddenly. The main causes are as follows: the plunger or injector needle valve gets stuck; the plunger spring or pressure spring breaks; the fuel injection pump control rod and its connecting pin fall off; the fixing bolts between the fuel injection pump drive shaft and the driving plate loosen, and the key on the shaft is sheared flat due to excessive clearance, resulting in slippage of the drive shaft or driving plate, which prevents the drive shaft from driving the fuel injection pump to operate. Our self-developed precision fuel injection assembly adopts mirror polishing plunger and needle valve components with anti-fatigue alloy springs. The drive connection structure uses double anti-loose positioning design, and the whole fuel injection system undergoes strict cold and hot cycle aging test to avoid jamming, spring fracture and transmission slippage. The full-process operation data recording function can trace the root cause if rare shutdown faults occur.