Service manual

FUEL INJECTORS
INSPECTING SPRAY PATTERN
1. Operate the hand lever of the nozzle tester at intervals of
one stroke per second to check if the fuel is injected cor-
rectly in its axial direction. A nozzle is defective
if it
injects fuel in an oblique direction or in several separate
strips. Also, a spray in the fonn
of particles indicates a
defect. These defects may sometimes be caused by clog-
ging
with dust and, therefore, all parts should be carefully
cleaned before reassembly. (Care should be taken not to
expose ones skin to this spray
as it may penetrate the skin
and cause infection.) .
,~,
\~
I \\,'
! II: I~I
NORMAL '1':"\ FAULTY ANGLE FAULTY DIRECTION
2. Apply the pressure of 115 kglcm2 (16351b/in2) to nozzle
by operating the hand lever, and check the drips from the
nozzle tip.
If it drips or has a large accumulation of fuel
on the bottom, it is considered defective and should be
replaced. A very small amount
of fuel may sometimes
remain on the tip
of the nozzle; however, this does not
mm-lrr ~ "",0-'" M
CORRECT W AFTER DRIP TEST • WRONG
DISASSEMBLING AND INSPECTING
1. Clamp the nozzle holder in a vise, then remove the
cap nut.
2. Remove the pressure adjusting screw, then pull out the
upper seat, spring and the push rod.
3. Clamp the nozzle holder in a vise, remove the nozzle nut
then pull the nozzle out.
4. Clean the disassembled parts with clean diesel fuel, then
remove the carbon adhering on the nozzle.
NOTE: Do not use a metal tool to remove the carbon.
S. After cleaning, check to see if the needle valve comes
down into the valve seat by its own weight when setting
the nozzle body upright position and inserting needle
valve.
6. Check that
there is no flaw or other damage on mating
surfaces and sliding surfaces
of nozzle body and needle
valve and,
if present, replace the nozzle assembly.
NOZZLE BODY
TORQUE
WRENCH
ASSEMBLING
Assemble in the reverse order of disassembly, noting the fol-
lowing points:
1. To assemble the nozzle and nozzle holder, first assemble
the pressure adjusting
nut side, and temporarily tighten the
nut. Mount the nozzle
and set the needle valve to proper
position, then mount
the nozzle nut.
2. After the nozzle and nozzle holder have been assembled,
check the injection starting pressure and spray condition.
Nozzle Nut Tightening Torque
71Bn1C 8 -10 m-kg (58 -72ft-lb)
Cap Nut Tightening Torque
71 B 4 - 5 m-kg (29 - 36 ft-lb)
@ ___ NUT
:;---;:: INJECTOR RETURN
BANJO BOLT-i
GASKETS ..... ~
~ LINE
-WASHER
NUT-~
BODY
CD
SCREW~
NOZZLE SPRING ~
UPPER SEAT
BRUSH ROD
NOZZLE BODY
---t.IOZZLE
"""'''-'''-~ NUT
BODY NUT
~~ 71C INJECTOR
INSTALLING
CONNECTOR
71 B INJECTOR
Install the nozzle and nozzle holder assembly in the reverse
order
of removal, noting the following points:
1. When installing the nozzle and nozzle holder assembly,
use a new copper washer.
2.
71 B TIghten the nozzle and nozzle holder assembly to
the specified torque.
Switch back and forth between the
nuts; do not tighten
one completely with the other loose.
Tightening Torque
71 B 1.6 - 2.4 m-kg (11.6 -17.4 ft-lb)
Tightening Torque
71C (27mm) 6.0-7.0m-kg(43-51ft-lb)
Engines & Generators
33