Service manual
FUEL
INJECTORS
REMOVING
THE
INJECTORS
NOTE:
Injector must be serviced in a "clean room" environ-
ment.
1. Disconnect the high pressure lines from the injectors and
loosen the lines at their attachment to the injection pump
and move them out
of
the way
of
the injectors. Avoid
bending the lines.
2.
Remove the fuel return line in its entirety from the top
of
the injectors. Take care not to lose the two sealing wash-
ers and banjo bolt that attaches the fuel return line to each
injector.
3. Unscrew the injector from the cylinder head using a suit-
able 27
mm
deep socket.
NOTE:
Clean the area around the base
of
the injector
prior to lifting it out
of
the cylinder head to help prevent
any rust
or
debris from falling down into the injector
hole.
If
the injector will not lift out easily and is held in
by carbon build up
or
the
like,
work the injector side to
side with the aid
of
the socket wrench to free it and then
lift it out.
4. The injector seats in the cylinder head on a copper seal-
ing washer. This washer should be removed with the
injector and replaced with a new washer when the injec-
tor is reinstalled.
INJECTION
TESTING/ADJUSTMENT
1.
Using the nozzle tester, check the spray pattern and injec-
tion starting pressure
of
nozzle and,
if
it exceeds the limit,
adjust or replace the nozzle.
When
using nozzle tester,
take the following precautions:
A
CAUTION:
The
spray
injected
from
the
nozzle
is
of
such
velocity
that
it
may
penetrate
deeply
into
the
skin
of
fingers
and
hands,
destroying
tissue.
If
it
enters
the
bloodstream,
it
may
cause
blood
pOisoning.
a.
If
the diesel fuel
of
the nozzle tester is discolored,
replace it.
At
the same time, clean or replace the filter.
b. Set the nozzle tester in a clean place where there is no
dust or dirt.
INJECTION
PRESSURE
TEST
c. Mount the nozzle and nozzle holder on the nozzle
tester.
d.
Use the fuel at the approximate temperature
of
68° F
(20
0
C).
e. Operate the hand lever
of
nozzle tester several times to
bleed the air in the nozzle line, then move the hand
lever at intervals
of
one stroke per second while read-
ing the injection starting pressure.
Injector
Starting
Pressure
1,920
Ib/in'
(135
kg/em')
f.
If
the fuel injection starting pressure is not within the
specification, it can
be
adjusted by removing or adding
shims in the injector body to achieve proper pressure.
NOTE:
The shims are available in
27
kinds ranging
from
0.5
mm
to 1.54
mm
at
0.02
increments.
An
incre-
ment
of
0.4
mm
causes the starting pressure to rise by
approximately
68 Ib/in
2
(4.8
kg/cm2).
SHIM
!
SHIM
THICKNESS
~t
0.1
mm
0.2mm
0.3mm
0.5mm
When replacing the shim, grip the retaining nut in a
vise and remove the body with a wrench. Tighten the
retaining nut to the specified torque.
INJECTOR_
Engines & Generators
34