1. Engine: During major maintenance, it is first necessary to check whether the engine has abnormal sound, jitter and other phenomena in the low, medium and high speed range to determine the current state of the engine. Then the maintenance technician will disassemble and clean the engine according to the actual situation. The main cleaning items include carbon deposit, glue deposit and scale, and at the same time, the oil circuit, oil pan, valve, oil seal, spark plug and other parts should be cleaned.
In addition, hardware such as cylinders, intake and exhaust manifolds, silencers, water pumps, air compressors, oil pumps, oil filters, oil tanks, etc. Tests should be conducted to ensure that the system is in good condition or working normally. General vehicles only need to be cleaned and descaled, and the bolts should be tightened. Some faulty vehicles need to be replaced with new accessories.
2. Gear box:
First of all, it is necessary to check the clutch for manual transmission vehicles, and cleaning and descaling are also necessary. Secondly, the stroke of the clutch pedal should be readjusted and reset, and the clutch pedal lubricant should be added. Whether it is manual or automatic, it is necessary to check the transmission, oil the gear, re-tighten the flywheel housing bolt and the transmission housing, and replace it if it is damaged, but this situation is rare.
The next step is to check whether the drive shaft is bent. Fix it if you can. If it can't be repaired, it needs to be replaced to avoid leaving hidden dangers. At the same time, check whether the tightness of the transmission shaft and telescopic sleeve is up to standard, check the intermediate shaft and bracket and oil them. It should be noted here that transmission oil needs to be added according to different brands and models. For example, Chevrolet Cruze, it is best to change it every 30,000 kilometers. Although BMW claims to be free to add it for life, it is recommended to change the gearbox oil about 654.38+10,000 kilometers.
3. Chassis:
Chassis maintenance mainly includes suspension, front and rear axles and braking system. First, check the hardware to ensure that there is no wear or other damage, then reinforce and straighten all hardware, and then add and replace damping fluid, brake oil, lubricating oil, etc. At the same time, check and reinforce the front and rear bumpers, trailer hooks and other body parts. The brake system needs to focus on checking whether the brake pads and brake discs need to be repaired or replaced.
4, body accessories
The major maintenance of car body accessories includes whether tires, fenders, engine room covers, center console, seat belt components, seats, pedals and other parts are loose, whether the connecting buckles are aged and broken, and whether they are displaced. If there is no visible damage, they don't need to be replaced, they just need to be straightened and strengthened again. If the tire is badly worn, it needs to be replaced. In addition, the owner should check whether the seat and seat belt components are reinforced after the maintenance is completed.
5. Electronic equipment
This link mainly includes routine inspection of driving computer, air conditioning system, battery, instrument panel and central control panel. Except the air conditioner needs to replace the filter element, other items do not need to be replaced without obvious faults, but the car mainly pays special attention to the battery state, and should be replaced in time when the power is insufficient.
6, other matters needing attention
When the vehicle is undergoing major maintenance, the main concern is the oil quality of the vehicle, such as brake oil, brake oil, steering auxiliary fluid, gearbox oil and damping fluid. Whether it was replaced before major maintenance, and how to replace it in a short time should be communicated with the service consultant in time, because in normal operation, technicians follow the standard process and will not detect the oil state, which is related to everyone's real money. You also need to communicate in advance, as well as spark plugs, batteries and all the parts you have replaced.
Finally, we should pay attention to the cycle of major maintenance. According to different brands and models, the time requirements are different. Usually it is four years or 60 thousand kilometers, but there are also brands or models outside this range. If the vehicle doesn't break down, I suggest you follow the timetable of the vehicle company, because major maintenance is very important to the health of the vehicle and should not be taken as a joke.