Technical information

- 35 -
5
74
75
(A-B) mm α mm
D (3LD)
mm
D (4LD)
mm
3LD
450, 451/S, 510, 510/S
58 ÷ 63 24° ÷ 26°
276 310
4LD
640, 705, 820
65 ÷ 70
4LD 820
a 2600 giri/1'
60 ÷ 65 22° ÷ 24°
Workshop Manual_3 - 4 LD_cod. ED0053025560_4° ed_ rev. 03
Fuel injection circuit
Advanced Injection references on the conveyor and
ywheel protection disk
A Piston reference at top dead centre
B Injection advance reference as to A
A ÷ B Distance in mm
C Reference of piston in injection advance position
α Reference in degrees
D Flywheel protection disk diameter
Note: 1
°
stands for 2.7 mm on dia. D= 310 mm; on dia. D =
276 mm, 1
°
stands for 2.4 mm.
ENGINES
Injector
Components:
1 Ring nut
2 Nozzle
3 Needle
4 Fitting
5 Nozzle bearing
6 Pressure rod
7 Spring
8 Spring seat
9 Union
10 Ring nut
Setting
Connect the injector to a manual pump and check that the
setting pressure is 190 ÷ 200 bars.
If necessary adjust, actuating the union 9.
While replacing the spring, the setting shall be carried out
at a pressure higher than 10 bars (200 ÷210 bars) in order to
counterbalance the running adjustments.
Check the needle valve seal by slowly activating the manual
pump up to abt. 170 bars.
In case of dripping, replace the nozzle.
Tighten the injector to the head at 15 Nm for 3LD 450, 3LD
451/S, 3 LD 510, 3 LD 510/S and at 20 Nm for 4LD 640,
4LD705, 4LD 820.
Note: A new injector is currently assembled, its components are
different, though the setting remains the same.