Diesel Fuel Injection Injector Nozzle

The engine cylinder head must be completely cleared of any leftover carbon deposits and impurities before a new nozzle is installed.

A clean installation environment is necessary for the fuel injector injection system optimization components to function effectively:

• Turn off the power and relieve the pressure: Unplug the car's battery's negative terminal, use a special pressure-relieving tool to relieve any remaining fuel pressure in the common rail pipe, and take care to prevent high-pressure fuel splashing when disassembling;
• Removing the previous nozzle: To avoid thread slippage, apply vertical upward force with the Lisle 45750 nozzle extractor after loosening the mounting screw counterclockwise with a torque wrench set to 25 N · m;
• Seat hole cleaning: To guarantee that gum deposits and metal debris are fully removed, inject 20 milliliters of Liqui Moly diesel system cleaning agent into the cylinder head fuel injector's installation hole, let it stand for five minutes, and then use 0.3 MPa compressed air to repeatedly blow up from the bottom of the seat hole three times.

method of meticulous cleaning
1. External purification: To dissolve the carbon deposits lodged in the needle valve, soak the removed old nozzle in CRC 05018, a specific fuel injector cleaning solvent, for 30 minutes. After that, put it in an ultrasonic cleaner set at 60 °C (frequency 40 kHz) for 10 minutes to completely clear the nozzle hole of microblockages;

2. Treatment of the contact surface: Apply Loctite 5920 high-temperature sealant uniformly to the conical surface of the new nozzle after dipping non-woven fabric into 99.9% pure isopropanol and wiping the cylinder head's installation surface in a single direction (do not rub back and forth to avoid scratches). For first curing, the coating thickness must be carefully maintained within 0.1 mm, and it must be left to stand for two minutes.

3. Control of dust: A sealed, dust-free area is ideal for the entire procedure (the Flexihood FH-300 type is advised). To remove particles adsorbed by static electricity, blow the nozzle body with an ion air pistol before to installation.
Setup and Confirmation

Tighten the fastening bolts twice in a staggered order after inserting the new nozzle vertically into the cylinder head seat hole (15 N · m the first time, 30 N · m the last time). Once the engine has started, read the fuel injection quantity data for each cylinder using the Bosch EPS 200 diagnostic tool. The deviation number should be less than 3%. Make sure there is no fuel leak by checking the sealing interface with the Wü rth SX500 leak detection spray when the engine is hot. The high-pressure fuel injector nozzle maintenance solution procedure has been finished thus far.