The installation and maintenance of throttle valve should pay attention to the following items!

The installation and maintenance of throttle valve should pay attention to the following items!

The throttle valve often needs to be operated, so it should be installed in a position easy to operate.

When installing, pay attention to the medium direction and the arrow direction marked on the valve body to keep consistent.

1、 The sources of throttle body deposits are complex, but they can be classified into the following categories:

1. Mechanical impurities in the oil or colloid, asphalt, carbon residue and other pollutants deposited in the throttle gap due to oxidation.

2. Due to the oil aging or extrusion, the charged molecules are generated, and there is potential difference on the metal surface of the throttling gap, so the molecules are adsorbed to the surface of the gap, forming a firm boundary adsorption layer. The thickness of the adsorption layer is generally 5 ~ 8 μ m, which affects the size of the throttling gap. When the above accumulation and adsorption increase to a certain thickness, they will be washed away by the liquid flow, and then re attached to the valve port. In this way, the pulsation of flow is formed.

3. When the valve port pressure difference is large, due to the high temperature of the valve port, the degree of liquid extrusion is enhanced, and the metal surface is more vulnerable to friction to form potential difference, so when the pressure difference is large, it is easy to block.

4. PCV exhaust gas source: the combustible mixture in the combustion chamber enters the crankcase through the piston clearance and mixes with oil vapor. In order to avoid dilution and oil contamination, the mixture is pumped into the intake port by the positive crankcase ventilation system (PCV) to participate in secondary combustion. After this part of exhaust gas enters the intake port, it will condense and form liquid phase due to the decrease of temperature. The "unstable components" in it will oxidize and condense at high temperature, and form oil fouling on the surface of throttle valve.

5. Deep lubricating oil of turbocharged compressor: for turbocharged engine, exhaust gas drive mode is generally adopted at present, that is, the turbine is driven by high-pressure exhaust gas generated from the exhaust port, and the compressor blade in the intake port is driven by coaxial to form inlet airflow pressurization. However, under the long-term and severe working conditions, the coaxial bearing is easy to cause the penetration and volatilization of lubricating oil, and then the aeration efficiency increases exponentially, which is more likely to form heavy oil pollution and aggravate the deposit attachment of throttle valve body.

6. Fuel vapor discharged from carbon canister: in the fuel vapor adsorbed by carbon canister of engine, as long as cyclopentadiene is easy to form throttle valve deposit, it can oxidize and condense to form colloidal oil scale under continuous high temperature.

Maintenance and cleaning of throttle valve

When the throttle valve (i.e. butterfly valve) is blocked by sediment, the throttle opening value will be disordered, and the engine can not stably and stably control its opening. If the opening value is too low, it will cause difficulty in starting, unstable idling or abnormal flameout; when the engine accelerates or decelerates, the throttle valve fails to respond in time, which will lead to acceleration delay or sudden acceleration.