alternator GW4D20 3701100-ED01A 02090201-028 4D20B for Used for the Great Wall Wing 5

Pre-installation Preparation

• Turn off the vehicle and wait for the engine to cool down completely. Disconnect the negative cable of the battery to eliminate the risk of short circuits or electric shock during installation.

• Verify that the model of the new 14V generator is compatible with the Great Wall Motor. Check the generator for external damage such as housing cracks and terminal oxidation.

• Clean the generator mounting bracket on the engine. Wipe off dust, oil, and debris from the surface with a cloth to ensure the mounting surface is flat and clean. Meanwhile, prepare thread-locking adhesive for later use.

Initial Fixation of the Generator Body

• Place the new generator steadily on the mounting bracket and align it with the bolt holes on the bracket. Insert the matching bolts through the mounting holes to initially fix the generator, but do not fully tighten them. Leave a certain amount of movement space to facilitate subsequent adjustment of the pulley position for adapting to the drive belt. If the mounting surface is slightly uneven, use thin metal shims for fine adjustment to ensure the generator body is stably placed.

Connecting Electrical Circuits

• It is recommended to mark the wires when removing the old generator. When installing the new generator, connect the power wires, control wires, and other plugs and terminals according to the marks. Tighten the fixing nuts of the output cables with a wrench, and apply a small amount of thread-locking adhesive to the connections to prevent loosening. Distinguish between positive and negative poles during wiring to avoid reversing them, which may burn out the generator rectifier or vehicle electrical appliances. At the same time, clean the oxides on the wiring terminals and do not pull the wires to prevent wire breakage or poor contact.

Installing and Adjusting the Drive Belt

• Fit the drive belt onto the generator pulley and the corresponding engine pulley in sequence. Use a belt tensioner tool to adjust the belt tension. The standard for normal tension is that pressing the belt produces a deflection of 1-2 centimeters. An overly loose belt is prone to slipping and affects power generation efficiency, while an overly tight belt will accelerate the wear of the generator bearings and the belt itself. After adjustment, manually rotate the pulley to confirm that the belt fits properly without deviation or jamming.

Tightening and Rechecking the Installation

• Use a torque wrench to evenly tighten the generator's fixing bolts diagonally according to the torque specified for Great Wall models (generally 20-30N·m for most passenger cars, subject to the vehicle maintenance manual). Ensure the generator body is firmly fixed to the bracket to prevent loosening due to vibration during vehicle operation. Then recheck whether the wire plugs are securely inserted and the belt is properly installed. After confirming no issues, reconnect the negative battery terminal.

Test Operation

• Start the vehicle and observe whether the charging indicator light on the instrument panel turns off normally. At the same time, use a multimeter to measure the voltage across the battery. When a 14V generator is working normally, the voltage is usually stable between 13.5-14.5V. If the indicator light works normally and the voltage is stable, the installation is qualified. If abnormalities occur, stop the vehicle to check and troubleshoot issues such as wiring connections and belt tension.

1. Bottom Lines for Safe Operation

• Disconnect the negative battery terminal throughout the entire process and never reconnect it before the installation is completed to completely avoid the risk of short circuits or electric shock.

• Avoid touching high-temperature engine components and rotating parts during operation. Be sure to clear tools before starting the vehicle after installation to prevent them from being caught in mechanical structures.

• Use tools of matching specifications (such as socket wrenches of corresponding models, torque wrenches). Never tighten bolts with brute force to avoid damaging the mounting bracket or generator housing.

2. Requirements for Installation Accuracy

• The generator model must be compatible with the specific Great Wall vehicle model. Verify that the voltage (14V), mounting hole positions, and pulley specifications are consistent to prevent installation failure or abnormal operation.

• Tighten the fixing bolts evenly and diagonally according to the torque specified for the vehicle model (generally 20-30N·m, subject to the vehicle maintenance manual). Thread-locking adhesive can be applied to key bolts for reinforcement.

• Strictly control the belt tension to a "deflection of 1-2 centimeters when pressed". After adjustment, manually rotate the pulley to confirm no deviation or jamming, preventing slipping due to loose tension or bearing wear due to excessive tension.

3. Wiring Standards

• Before wiring, refer to the marks made during old generator removal (be sure to mark when disassembling old parts). Distinguish between positive and negative poles and wire functions. Never reverse the connection of power wires and control wires, as this will burn out the generator rectifier or vehicle electrical appliances.

• Ensure wiring terminals are clean and free of oxidation. Avoid pulling wires when tightening fixing nuts to prevent wire breakage; wrap the connections with a small amount of insulating tape to improve stability.

• Do not plug or unplug wires while the generator is running. Recheck all connectors one by one before testing to ensure no looseness or exposed metal contacts.

4. Operation Inspection and Maintenance

• After the first start, first observe whether the charging indicator light turns off normally, then use a multimeter to measure the battery voltage (13.5-14.5V is normal). Only drive normally if there are no abnormalities.

• Pay attention to the generator's operating noise in the short term after installation. If there is abnormal noise or vibration, promptly check the belt tension or bolt tightness.

• Regularly clean dust and oil from the generator surface to avoid poor heat dissipation; recheck wire connectors and fixing bolts after long-term use to prevent loosening due to vibration.

5. Reminders for Special Scenarios

• If bracket deformation, belt aging/cracking, or tensioner jamming is found when removing the old generator, replace them simultaneously to avoid affecting the service life of the new generator.

• Those without experience in passenger car electrical maintenance are not recommended to operate independently. Prioritize contacting Great Wall Motors after-sales service or professional maintenance personnel to avoid secondary damage.

References：

AutoMaster

Yiche (BitAuto)

Autohome and PCauto