Reason & maintenance method of generator start failure,excavator start failure

Posted on:2021-02-06       View:24

I.Overview

1.Trouble phenomenon: The vehicle can generally start normally when the vehicle is cold. However, when the vehicle is restarted in a short time after the operation is stopped, it will be difficult to start. ---The starting motor will stop after a few revolutions, and it will start normally after several more starts or wait a few minutes.

2.The cause of the fault: After investigation, the fault was caused by the alteration of the generator and the lowering of the power generation speed in response to poor start-up in cold regions in winter, which caused some vehicles to generate electricity before the start of the generator, resulting in over-start protection. Intervention in advance, the vehicle cannot start.

3.Countermeasures: Replace the generators whose speed has not been reduced before countermeasures.

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II. Preparation before renovation

1.Preparation before modification and replacement

(1) To confirm the placement of modified vehicles, refer to the figure below.

Park the machine on a firm and level ground.

Choose a place where there is no danger of falling rocks or landslides, or if the terrain is low, there is no danger of flooding.

Lower the working device completely to the ground.

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When leaving the machine, move the safety lock lever ① to the locked position (L), and then turn off the engine.

Set the key of the battery disconnect switch to OFF (closed) or disconnect the battery negative (-) cable. Turn off the engine.

In order to prevent unauthorized personnel from moving the machine, close the door of the cab and lock all devices with a key. To remove the key, take it with you and put it in the designated place.

(2) Please confirm that the engine and related parts are sufficiently cooled down before performing the replacement operation.

2.Precautions when repairing and replacing

Please pay attention to safety when working.

For the essentials not recorded in this service information, please refer to the decoration manual and operation and maintenance manual.

For the tightening torque of bolts and nuts that are not indicated, please refer to the standard of the decoration manual.

III. Revised essentials

Method for judging poor start of the generator

 

1.Judgment method and steps for generator start:

Start the engine without injection

(1) Press [4] + [1] → [2] → [3] to enter the service menu, and set the non-spray mode according to the following steps 2

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 Points to note:

(2) After setting to the non-injection mode, turn the key to the START position to start the engine. Note that the starting time should not exceed 20s, otherwise it will cause damage to the starting motor and battery

(3) In the process of starting, observe whether the engine suddenly stops after a few revolutions (instantly the key switch is in the START position) and the generator generates power in advance to prevent the second start.

(4) If the above phenomenon occurs, the generator will generate NG in advance, otherwise the generator is OK

The cylinder cut off & start the engine

(1) Press [4] + [1] → [2] → [3] to enter the service menu, and perform cylinder cut-off test according to the following steps

 Points to note:

(2) After setting to the non-cylinder mode, turn the key to the START position to start the engine. Note that the starting time cannot exceed 20s, otherwise it will cause damage to the starting motor and battery.

(3) In the process of starting, observe whether the engine suddenly stops after a few revolutions (instantly the key switch is in the START position) and the generator generates power in advance to prevent the second start.

(4) If the above phenomenon occurs, the generator will generate NG in advance, otherwise the generator is OK

※Note: If the generator is NG judged by the above, please follow the steps below to replace the rectifier or generator.

Rectifier replacement method

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Generator replacement method

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Replace the new product generator assembly

1. Assembling the new product generator assembly is the opposite of the disassembly steps;

2. Assemble the V-belt to ensure smoothness and no distortion, and completely in the wheel groove;

3. Adjust the tension force of the V-belt according to the following method;发电机7.jpg

1. Check the parts of each disassembly assembly to see if there is any looseness or omission of tightening;

2. Start the engine, run and inspect for 20 minutes, and observe again; check whether the V-belt and fan blades rotate normally. If there is no abnormality, the operation ends.