What to do if the tractor's engine speed is unstable

In the process of running the tractor will encounter the phenomenon of unstable engine speed, the need for timely removal, otherwise it may cause serious consequences. The specific exclusion method can refer to the following three points:

1. The tractor runs unsteadily under heavier load conditions, and the tractor runs more smoothly when it is empty or on a downhill slope. The fuel system should be checked to see if it is blocked and the oil is not flowing smoothly.

2. Remove the observation hole cover on the gear chamber cover, start the engine, and use the screwdriver to hold the speed lever to fix it in a certain position. If the operation is stable at this time, the fault may be in the governor section. Check as follows: First of all, check if there are any loose parts at the joints of the engine's external speed-regulating mechanism. Otherwise, remove the loose obstacles. After removal, the operation is still not stable. The gear chamber cover should be removed to check the internal structure of the governor. The internal structure of the governor should mainly check whether the gear shaft of the governor and the body are loose and whether the bifurcation of the short arm of the speed governor is uneven or not. If the two forks are seriously worn, a 1 mm thick paper spacer can be added between the speed governing disc and the unidirectional thrust bearing. Note that the paper pad should not be too thick, otherwise it will reduce the maximum engine speed and reduce the power. If after the above-mentioned treatment, unstable rotation speed can not be eliminated, it should also check whether the speed regulation lever is blocked, whether the injection pump plunger adjustment arm is excessive in the speed adjustment lever fork groove, and the plunger rotates in the plunger sleeve. Whether it is blocked or inflexible.

3. Hold down the speed lever with a screwdriver. If the operation is not stable, it means that the fault is not in the governor section. Check the fuel system. First of all, loosen the oil pipe joint nut on the fuel injection pump. If any air bubbles are found, it can be confirmed that the air in the oil passage enters the air. Check whether the oil pipe is broken and whether the pipe joint nut is loosened. Special attention should be paid to the fuel pump outlet valve gasket. Whether it is cracked or tightly sealed, whether the plunger of the oil pump plunger is loose or not. After the above check and repair, the engine speed is still not smooth, the injector can be removed from the cylinder head, and replaced with a new fuel injector for testing. If the fault is solved, the fault is on the injector; the injector can also be removed and reinstalled on the high-pressure fuel pipe, and the engine can be shaken to observe the injection of the injector. If there is poor atomization, there is a drop of oil or a stuck needle, which can be ground or replaced.