Today, I will introduce some precautions for car repairs in the repair shop. If the parts such as fuel filter, oil filter, air filter, hydraulic oil filter and various filters are too dirty, it will cause filtration. The effect becomes worse. Excessive impurities enter the cylinder of the oil circuit, which will aggravate the wear of the parts and increase the possibility of failure; if it is severely blocked, it will also cause the vehicle to fail to work normally.

One, afraid of being “dirty”

If the parts such as fuel filter, oil filter, air filter, hydraulic oil filter and various filters are too dirty, the filtering effect will be deteriorated. Excessive impurities will enter the cylinder of the oil circuit and aggravate it. The wear and tear of mechanical parts increases the possibility of failure; if it is severely blocked, it will also cause the vehicle to fail to work normally. Dirty parts such as water tank heat sink, air-cooled engine block and cylinder head heat sink, and cooler heat sink will cause poor heat dissipation and excessive temperature. Therefore, for such “fear of dirt” parts must be cleaned and maintained in time.

Two. Afraid of “hot”

The engine piston temperature is too high, which will easily lead to overheating and melting, resulting in cylinder holding; overheating of rubber seals, triangle tape, tires, etc., is prone to premature aging, performance degradation, and shortening of service life; electrical equipment such as starters, generators, regulators, etc. If the coil is overheated, it is easy to burn and scrap; the vehicle bearing should be kept at a proper temperature. If overheated, the lubricating oil will quickly deteriorate, causing the bearing to burn out and the vehicle to be damaged.

Three, afraid of “string”

Various coupling parts in the diesel engine fuel system, the driving and driven gear in the drive axle main reducer, the hydraulic control valve block and valve stem, the spool and valve sleeve in the full hydraulic steering gear, etc. These mating parts are manufactured at the time of manufacturing. After special processing and grinding in pairs, the coordination is very precise. It is always used in pairs during the life of use and must not be interchangeable. Some cooperating parts, such as piston and cylinder liner, bearing bush and journal, valve and valve seat, connecting rod head cover and shaft, etc., after a period of friction, they are relatively well matched. You should also pay attention to it during maintenance. Assemble in pairs, don’t “catch” each other.

Fourth, afraid of “reverse”

The engine cylinder head gasket cannot be installed backwards during installation, otherwise it will cause premature ablation and damage to the cylinder head gasket; some special-shaped piston rings cannot be installed reversely, and should be assembled according to the requirements of different models; the engine fan blades should also be installed in a direction Requirements, the fan is generally divided into two types: exhaust and suction. It cannot be reversed, otherwise it will cause poor heat dissipation and high temperature of the engine; for tires with directional patterns, such as herringbone tires, the ground impressions after installation should be The tip of the word points to the back to ensure greater driving force. For the two tires installed in parallel, different models have different requirements, so they cannot be installed at will.

Five. Fear of “lack”

When servicing vehicles, some small parts may be omitted due to negligence. Some people even think that it does not matter whether they are installed or not. This is very dangerous and harmful. Engine valve lock plates should be installed in pairs, if missing or missing, it will cause the valve to lose control and damage the pistons and other parts; engine connecting rod bolts, flywheel bolts, cotter pins installed on the drive shaft bolts, locking screws, safety plates or If the spring washer and other anti-loosening devices are missing, they may cause serious failures during use; if the oil nozzle used to lubricate the gears in the engine timing gear chamber is missing, it will cause serious oil leakage in that place and cause the engine The oil pressure is too low; the loss of the water tank cover, the oil port cover, and the fuel tank cover will cause the intrusion of sand, gravel, dust, etc., and aggravate the wear of various parts.

Six, afraid of “oil”

The paper filter element of the engine dry air filter has strong moisture absorption. If it is stained with oil, it is easy to draw a higher concentration of mixed gas into the cylinder, resulting in insufficient air volume, increased fuel consumption, and reduced engine power. Diesel engines may also Causes “speeding”; if the triangle tape is stained with oil, it will accelerate its corrosion and aging, and at the same time, it will easily slip, resulting in a decrease in transmission efficiency; brake shoes, dry clutch friction linings, brake bands, etc., if they are stained with oil It is easy to cause slippage and poor work, thereby threatening driving safety; if the starter motor and generator carbon brushes are stained with oil, poor contact will result in insufficient starter motor power and low generator voltage. Tire rubber is very sensitive to oil corrosion. Contact with oil will soften or peel the rubber. Short-term contact will cause abnormal damage or even serious damage to the tire.

Seven, afraid of “washing”

Some people who are new to driving or repairing may think that all parts and accessories need to be cleaned. In fact, this understanding is one-sided. For the paper air filter element of the engine, when the dust on it is removed, it cannot be cleaned with any oil. You only need to tap it with your hands or blow high-pressure air through the filter element. It is also not suitable for leather parts. To clean with oil, just wipe it with a clean cloth.

Eight. Afraid of “pressure”

If the tire casing is stored for a long time and is not turned over in time, it will deform due to extrusion, which will affect the service life; the paper filter element of the air filter and fuel filter will be greatly deformed if it is squeezed It cannot reliably filter; the rubber oil seal, triangle tape, tubing, etc. cannot be squeezed, otherwise it will also deform and affect normal use.

Nine, afraid of being “near the fire”

Rubber products such as tires, triangle tape, cylinder liner water blocking ring, rubber oil seal, etc., if they are close to the fire source, will be prone to deterioration or damage. On the other hand, they may also cause fire accidents. Especially for some diesel vehicles, it is difficult to start in the severe cold in winter, and some drivers often use blowtorch to heat, so it is necessary to prevent burning of lines and oil circuits.

Ten, afraid of “repetition”

Some parts are supposed to be used once, but individual drivers or repairers reuse them in order to save money or because they don’t understand the “taboo”, which can easily lead to accidents. Generally speaking, engine connecting rod bolts, nuts, imported diesel fuel injector fixing bolts, cylinder liner water blocking ring, sealing copper gasket, various oil seals and sealing rings of the hydraulic system, and important parts of the pin, split pin and other parts are removed It must be replaced with a new product; for the engine cylinder head gasket, although no damage was found during the inspection, the new product should be replaced because the old product has poor elasticity, poor sealing, and easy ablation damage. It needs to be replaced after a short period of use, which is time-consuming and labor-intensive. New products should be replaced as much as possible.