106971-0812 ZEXEL 9 400 618 651 BOSCH INJECTION-PUMP ASSEMBLY 9400618651 1069710812 1670097107

Fuel Injection Nozzles
Disassembly of Fuel Injection Nozzles
Inspection of Fuel Injection Nozzles
Check each fuel injection nozzle for the following, and if defects are found, repair or replace the fuel injection nozzle.(1) Inspection of injection start pressure(a) Install each fuel injection nozzle on the nozzle tester, and move the handle up and down to release air.(b) Operate the handle of the tester at a rate of about 1 stroke per second, and read the indication on the pressure gage. The indication rises slowly, and the indicator oscillates during spraying. To obtain the injection start pressure value, read the indication when the indicator starts to oscillate.
Inspection of fuel injection nozzle valve opening(c) If the injection start pressure deviates significantly from the standard value, disassemble the fuel injection nozzle, and make an adjustment by changing the washer thickness. 0.1 mm [0.0039 in.] thickness of shims will change the injection pressure 0.98 Mpa (10 kgf/cm2 [142 psi]. The shims are available in 10 different thickness from 1.25 to 1.70 mm [0.0492 to 0.0669 in.] increment of 0.05 mm [0.0020 in.]
Never tap the tip of the nozzle tip when removing the nozzle tip.
Replacement of fuel injection nozzle tip(2) Inspection of fuel injection nozzle spray pattern(a) When inspecting each fuel injection nozzle with the nozzle tester, also check the nozzle for clogs, spray pattern and leakage.(b) Make sure that the fuel is sprayed straight from the nozzle when the handle of the tester is operated at a rate of about 1 stroke per second.
Inspection of spray pattern of fuel injection nozzle(3) Cleaning and replacement of faulty nozzles(a) Loosen the nozzle retaining nut, remove the nozzle tip, and clean the needle valve and body.
Never tap the tip of the nozzle tip when removing the nozzle tip.
(b) Use a fresh cleaning solution to clean the needle valve and body. After cleaning, assemble the needle valve and body in clean diesel fuel. The needle valve and body are precision finished. Handle them carefully, and do not change the combination of parts.
Cleaning of fuel injection nozzle tip(c) Tighten the nozzle retaining nut on the nozzle tip to the specified torque.(d) If the spray pattern is still not acceptable after adjustment and cleaning, replace the nozzle tip. (a) Never touch the sliding surface of the needle valve.(b) When installing a new nozzle tip, remove the seal film (synthetic resin film), and slide needle valve in the nozzle in a fresh cleaning solution to remove anti-rust oil coating thoroughly from the new nozzleReassembly of Fuel Injection Nozzles