Automobile AC generator SMW251442, ALQ2418BS 4G63T UFZ1929M-1，77AL151,ALQ2418BS suitable for Great Wall Harvard H3

Pre-installation Preparation

• Tool and Accessory Preparation: Prepare tools including socket wrenches, box-end wrenches, screwdrivers, and rags. Confirm that the model of the new 12V generator is compatible with Haval H3. Check that the generator housing is free of damage and the terminal blocks are free of oxidation and rust. Meanwhile, prepare matching fixing bolts, gaskets, and other accessories to avoid incompatibility during installation.

• Safety Protection Operations: Park the vehicle on a flat surface, pull the handbrake, turn off the engine, and pull out the key. Be sure to disconnect the negative connection wire of the car battery to prevent short circuits that may damage electronic components or cause electric shock risks during installation.

• Clean the Installation Area: If the old generator was just removed, wipe the dust, oil, and debris from the installation position with a rag. Ensure the mounting surface is flat and clean to reduce vibration and malfunctions caused by poor contact when the generator works later.

Core Installation Operations

• Preliminary Fixation of the Generator: Place the new generator stably on the mounting bracket in the engine compartment. Align it with the bolt holes on the bracket and initially fix it with fixing bolts without fully tightening—reserve space for subsequent adjustment of belt tension to avoid being unable to adjust the belt tightness after premature full tightening.

• Standardized Wiring Connection: The Haval H3 generator is equipped with interfaces such as output wires and control wires. Before installation, you can distinguish the wires by referring to the wiring position of the old generator or the vehicle wiring diagram. Insert each wire connector into the corresponding terminal of the generator to ensure full clamping. If the terminal has slight oxidation, wipe it clean first; apply a small amount of conductive paste if necessary to prevent poor contact. Strictly prohibit reverse connection of positive and negative wires to avoid burning the generator or the vehicle circuit.

• Belt Installation and Tension Adjustment: Accurately fit the drive belt onto the generator pulley and the corresponding engine pulley. Adjust the tension using the belt tensioner. Press the middle of the belt by hand—if it can sink 10-15mm, the tension is appropriate. An overly loose belt may slip and affect power generation; an overly tight one will accelerate the wear of generator bearings and belt aging. If the old belt is cracked or aged, it is recommended to replace it at the same time.

• Tighten All Bolts: After confirming that the belt tension meets the standard and the wiring is correct, use a wrench to fully tighten the generator’s fixing bolts in a diagonal and evenly forceful manner. Prevent bolt loosening due to vibration during vehicle driving, which may affect the stability of the generator.

Post-installation Inspection

• Restore the Circuit and Conduct Initial Check: Reconnect the negative wire of the battery and recheck all wire connectors and fixing bolts to confirm there are no loosening, incorrect connection, or other issues.

• Start-up Test: After starting the vehicle, observe the charging indicator light on the instrument panel. If the indicator light goes out normally, the generator is basically working properly. Meanwhile, you can turn on electrical equipment such as vehicle lights and air conditioning to test stable operation. If the indicator light remains on or the generator produces abnormal noise or odor, turn off the engine immediately and check the belt tension or wiring connection for problems. In addition, you can use a multimeter to measure the battery voltage at idle speed—the normal voltage should be between 13.5-14.5V to further confirm that the generator is charging normally.

1. Safe Operation Red Lines

• Disconnect the battery’s negative terminal first before the entire installation process. Live working is strictly prohibited to avoid short circuits that may burn core electronic components such as the generator regulator and ECU.

• During operation, keep tools away from exposed wiring harnesses and sensors (e.g., crankshaft position sensor) in the engine compartment to prevent scratching the wire insulation layer or interfering with signals.

• During start-up testing, keep hands and clothing away from rotating parts such as pulleys and fans. At the same time, avoid touching the generator housing (which will heat up after operation) to prevent scalding or entanglement.

2. Compatibility and Installation Accuracy Requirements

• The generator model must match the original factory specifications of Haval H3 (e.g., compatible with engine models such as 4G63/4G64) to avoid abnormal charging or even battery damage due to mismatched voltage and power.

• Use original specifications (usually 8.8-grade) for fixing bolts. Tighten them following the "diagonal and uniform" principle with moderate force—preventing loosening from vibration while avoiding bolt thread stripping or mounting bracket deformation.

• Thoroughly clean the mounting surface to ensure the generator fits tightly with the bracket without gaps or skew. Otherwise, it will intensify operational vibration and lead to premature bearing wear.

3. Standardized Wiring Connection

• Strictly refer to the wiring position of the old generator or the vehicle wiring diagram to distinguish between the output wire (B+), excitation wire (F), etc. Reverse connection of positive and negative poles is strictly prohibited, as it is one of the main causes of generator burnout.

• Ensure wiring terminals are fully inserted and locked. If there is an oxide layer on the terminals, gently polish it off with fine sandpaper; apply conductive paste if necessary to improve contact conductivity and avoid overheating or sparking.

• Route wires away from high-temperature areas such as the exhaust pipe and turbocharger. Secure excess wires to the engine compartment bracket with cable ties to prevent wire wear and insulation damage caused by long-term vibration.

References：

1. Haval H3 Forum on Autohome

   This serves as the core source for practical operations. Car owners of the Haval H3 on the forum have posted hands - on articles about the disassembly and installation of the generator for the 2.5TCI model. These articles detail the generator disassembly and assembly steps including regulator replacement, such as removing the vacuum pump, separating the front and rear end covers of the generator, and fixing the regulator—operations specific to this model's installation. They also mention precautions like not omitting rubber gaskets during installation and ensuring the front end cover presses against the carbon brushes during fitting. It is a practical reference tailored to the Haval H3.

2. General Automobile Maintenance Q&A Section on Autohome

   The universal precautions for automobile generator installation published in this section are also applicable to the installation of the 12V generator for the Haval H3. These include disconnecting the negative electrode of the storage battery before installation to prevent short circuits, maintaining appropriate tension of the drive belt, and avoiding incorrect wiring to prevent damage to electronic components. It stands as an important reference for universal installation standards.

3. Automobile Encyclopedia Section on PCauto

   The summarized specifications here, such as generator installation wiring rules, standards for belt installation and tension adjustment, and methods to judge the working status via the charging indicator after installation, are universal guidelines for installing most 12V generators including that of the Haval H3. It can be used as a supplementary reference for the procedures and precautions during the installation of the Haval H3's generator.

4. Technical Documents on Mayiwenku

   The technical key points contained herein, such as the requirement that generator mounting bolts must match the specified model and be tightened to the designated torque, and that the generator installation position should be kept away from the high - temperature areas of the engine, are universal technical requirements for generator installation. They are also applicable to the installation operation of the 12V generator for the Haval H3.