Method of repairing machinery

Farmers who have used diesel generators generally know that the nozzle is one of the three precise pairs of diesel fuel supply system. Its normal service life is over one thousand hours. But due to improper use, often use hundreds of hours, even dozens of hours on the wear and tear card.

First, the main reasons for the oil injection nozzle stuck:

1. Diesel is not clean, there are impurities in the high pressure oil pipe, so that the needle valve couple is not strictly closed, the high pressure gas in the combustion room channeling, burning the needle valve couple. In addition, the dirt on the injector pressure regulating spring, tappet and other parts is moved to the upper part of the injector needle valve through the injector tappet, or the cotton rope and lead wire used to prevent oil leakage on the oil circuit enter the injector through the high pressure tubing, which will make the needle valve couple stuck.

2, the machine temperature is too high, the fuel injector cooling is poor, resulting in the needle valve even parts stuck. And the oil supply time is too late, too much cooling water scale or blockage, pump impeller end face wear, long-term engine overload and so on will make the engine overheating.

3. The oil outlet valve is worn, so that the oil injector stops spraying, and the phenomenon of oil dripping occurs, so that the nozzle burns coke and accumulates carbon, and the fault of sticking occurs.

4. When the fuel injector is installed, the gasket or gasket is damaged, resulting in air leakage, causing the local temperature of the fuel injector to be too high and stuck.

5, the injection pressure is too low, resulting in high pressure gas channeling in the combustion chamber;

6, parts manufacturing reasons, such as the cylinder head on the injector installation hole with the injector too tight, the needle valve body and the cylinder head on the installation hole clearance is too small, cylinder head injector installation hole processing is too deep.

Two, the nozzle stuck repair method: first put the stuck nozzle into diesel or oil heating, then take out the cloth wrapped, and then use the pliers to clamp the needle valve and slowly move, the needle valve from the needle valve body. Drop a small amount of cleaning oil in the needle valve body, so that the needle valve in the needle valve body repeated activity, until the needle valve can move freely in the needle valve body. If the sealing surface of the needle valve has burn marks, it should be ground with grinding paste. When grinding, pay attention to the amount of grinding paste and grinding time. Install the cleaned needle valve couple on the injector, and adjust the injection pressure can be used again.