If the engine control system is not adjusted properly, the engine will be overloaded, and the operating and walking speed will be reduced, and the performance of the excavator will not be able to be exerted. Excavator repair and adjustment of the engine control system must be carried out in accordance with regulations.
1. Engine control system assembly method Engine control system adjustment
1) Adjust the assembly length of the rod 2 to about 250mm.
2) In the above state, adjust the limit bolt so that the pedal is located at the upper end of the travel valve plunger 10. Note: Do not let the plunger be compressed.
3) After the rod 2 is assembled, hang the spring 7 between the rod 4 and the rod 8, and then adjust the rod 8 left and right to adjust the initial assembly length to 140mm.
4) The length from the end of the brace 6 to the threaded part is about 150mm, insert the fork rod 9, and then fix the brace on the bracket. At this time, in order to prevent the brace from sinking or detaching by more than 150 mm, adjust the insertion depth of the fork rod 9 or adjust the threaded part of the brace from left to right.
5) Fill the grease nozzle 5 with butter.
2. Engine speed adjustment method
(1) Check and precautions before adjustment. Tighten the bolt 5 to minimize the Lg of the head.
2) Set the start switch to the ON position and the engine control knob to the min position.
3) Assemble the pedal ties 9 and the engine control motor ties 10 as follows.
①Assemble the pedal bead 9 as shown in the figure.
② The brace 9 is not allowed to sag. Before fixing it to the bracket 2, pull the end with your hand, but don't use too much force.
③In the state where the adjusting rod 3 is in contact with the stop block 11, the brace 9 is fixed to the bracket. In order to prevent the lacing bars from sinking, after adjusting the thread left and right, tighten the fixing nuts on both sides at the same time.
(2) Speed adjustment in various operating modes 1) Engine control motor adjustment
① After the engine is started, the power mode is set to speed mode, and the automatic idle speed switch is set to the OFF position.
②Set the drive/work selector switch to the working position, and check whether the forward/backward joystick is in the neutral position.
③Turn the engine control knob to the maximum position.
④ Adjust the variable resistance with a screwdriver to make the engine speed within the range of (1750 ± 50) r/min.
⑤Turn the engine control knob from the minimum position to the maximum position, and operate the walking/work selector switch to make the maximum engine speed in this work mode turn to (1900 t 50)r/min.
Note: The speed difference when the engine speed changes from low to high may deviate from the speed difference when the engine speed changes from high to low.
2) Pedal valve adjustment.
① Put down the left lever (the pilot cut-off switch is in the ON position).
②According to the position of the travel/work selection switch, confirm whether it is the work mode or the travel mode. When in operation mode and walking mode, the pedal valve stroke is the largest, about 60mm.
Note: When in the operating mode, in order to retract the plunger, there must be a proper external force.
③After confirming, set the travel/work selector switch to the work position.
④ Slowly step on the pedal valve, adjust the speed to (1750 ± 50) r/min, adjust the length of the rocker shaft 6 so that the head contacts the plunger 4, and fix it with a nut.
⑤ Step on the pedal valve 2~3 times to check whether the engine speed is within the range of (1900±50) r/min.
(3) Automatic rate and speed adjustment
1) Automatic idle speed adjustment
①After the engine starts, set the engine speed control knob to the maximum position.
②Set the walking/work selector switch to the walking position, the automatic idling switch to the ON position, and the power mode is the I-speed mode.
③Use a screwdriver to adjust the variable resistance so that the engine speed is within the range of (1400±50)r/min.
2) II speed mode conversion adjustment
①After the engine starts, set the engine speed control knob to the maximum position.
②Set the walking/work selector switch to the walking position, the automatic rate switch to the OFF position, and the power mode is the I-speed mode. ③Adjust the variable resistance with a screwdriver to make the engine speed within the range of (1750 ± 50) r/min.
3) I speed mode speed adjustment
①After the engine starts, set the engine speed control knob to the maximum position.
②Set the start/work selector switch to the walking position, the automatic idling switch to the OFF position, and the power mode is the I-speed mode.
③Use a screwdriver to adjust the variable resistance so that the engine speed is within the range of (1600±50)t/min.
