Technical data

51
turn the fuel pump shaft in the end within the grooves position;
drain some fuel from the glass gauge;
rotate the fuel pump shaft slowly clockwise till the fuel goes up;
as soon as the fuel starts rising stop rotating the shaft and tighten the nuts;
check timing once again.
3.3.20. Changing the Fuel Injectors for the Pressure of Beginning the In-
jection and Fuel Atomisation Quality
Check the fuel injectors every 2,000 service hours of the diesel engine.
Remove the fuel injectors from the engine and check them on the test bench.
The fuel injector is considered to be in good order, if it atomises the fuel in the mist form
from all five holes of the atomizer, without drops flying out separately, continuous jets or conden-
sations. The beginning and end of the fuel injection shall be clear, no drops shall appear on the at-
omizer tip.
Check the atomisation quality at the frequency of 60-80 injections per minute.
Adjust the fuel injectors for the injection pressure of 3,132
+0.116
MPa (220
+8
kgf/cm
2
).
In case of poor fuel atomisation clean the atomizer from scale. To do this, disassemble
the fuel injector. Unscrew the cap in accordance with Fig. 30, loosen the lock nut 2 and unscrew
the adjusting screw 1 by 2-3 turns (loosening in such manner the spring), then turn out the atom-
izer nut and remove the atomizer. Dismantling the fuel injector in different order could cause
damage to the dowels centring atomizer.
Clean the atomizer from scale using a wooden scraper and clean the nozzle holes using a
special needle for cleaning the fuel injector atomizer holes or string with the diameter of 0.3 mm.
If the holes cannot be cleaned immediately, let the atomizer soak in gasoline for 10-15 min and
clean them again.
Wash the atomizer in pure gasoline and then in diesel fuel.
If the atomizer cannot restore its quality by washing, it shall be replaced with a new one.
Before mounting into the fuel injector, perform the depreservation of new atomizers by
washing them in gasoline or preheated diesel fuel.
Assemble the fuel injector in the reverse order. Adjust the pressure of beginning of the
injection by means of the adjusting screw. Lock the adjusting screw by tightening the lock nut and
screw the cap on the fuel injector.
Install the fuel injectors onto the engine. Tighten the bolts fastening the fuel injectors uni-
formly, in 2-3 operations. The final tightening torque shall be 14.75...18.44 lb.ft (2.0...2.5 kgf.m).