k. Thoroughly rinse the valve (4) in clean diesel
fuel before installing it in the valve body (3).
l. Examine the flat sealing surface of the valve
body (surface which contacts lower end of the holder
body) and make certain surface is clean and free of
scratches. This surface may be lapped, if necess-
ary, using lapping compound, castor oil, and a
After lapping, remove all traces of
lapping compound with clean diesel fuel.
m. Make certain that the bottom flat seating sur-
face of the nozzle holder body (15) is clean and in
good condition. Rinse the valve (4) and valve body
(3) in clean diesel fuel, then insert valve (4) into
position in the valve body (3). Place the valve body
(3) and valve (4) in position on the end of the nozzle
holder body and center the valve body with the holder
body (15). Install and tighten the nut (5) to a torque
of 40 to 60 inch-pounds.
It is important that the valve body be
centered in the nozzle retaining nut.
Use care while tightening the nozzle
retaining nut so that the valve body
remains centered in the nut.
n. If malfunctioning of the nozzle holder assembly
was not corrected by removal and cleaning of the
nozzle valve body and valve, disassemble and clean
the nozzle holder as follows:
(1) Clamp nozzle holder (15) assembly in a
holding fixture and remove the cap nut (10) and gas-
ket (11 ) from upper end of nozzle holder. Loosen
and remove the pressure adjusting screw locknut (8).
(2) Remove pressure adjusting screw (9),
spindle spring (12), and spindle (13).
(3) Remove nozzle retaining nut (5), and dis-
assemble the nozzle assembly.
(4) Place all parts in clean diesel fuel. Using
filtered compressed air, blow out the fuel passages
in the holder body.
(5) Visually inspect the parts for damage or
wear; replace necessary parts. Examine the flat
sealing surface of holder body (15) (surface which con-
tacts upper end of valve body) and make certain the
surface is clean and free from scratches. This sur-
face should be lapped if necessary, using lapping com-
pound, castor oil, and a lapping block. When lapping,
use care to keep the nozzle holder body square with
the lapping block to assure contact with the entire
area being resurfaced.
After lapping, remove all
traces of the lapping compound with clean diesel fuel
and dry with filtered compressed air.
(6) Examine the spindle spring (12). If the
spring is scratched or pitted, it must be replaced.
Also, the spring must be replaced if the ends have
worn. Always replace springs when rebuilding
(7) Rinse spindle (13) in clean fuel and insert
it into holder body (15). Place the spindle spring (12)
in position on spindle (13). Install pressure adjusting
screw (9), pressure adjusting screw locknut (8), cap
nut (1 O) and gasket (11); do not tighten at this time.
(8) Install nozzle valve (4), valve body (3), and
nozzle retaining nut (5). Tighten nut to a torque of
40 to 60 foot-pounds.
O. When rebuilding an injector assembly, the
nozzle assembly, spindle (13), spring (12), adjust-
ing screw (9), and all gaskets (2, 14, 11) must be
14-40. Test and Adjustment.
Keep hands away from nozzle tip when
popping a nozzle.
The finely atomized
fuel is ejected with sufficient force to
penetrate the skin and cause blood
a. Use diesel injector test set tool (table 2-1)
and lest and adjust each nozzle as follows
(1) Bolt or clamp base of nozzle tester to a
(2) Turn nozzle tester valve handle to the open
position. Loosen filler cap to prevent air lock in the
tester. Operate handle until fuel flows from end of
tester fuel line, then close valve.
(3) Install nozzle in tester and connect line.
Place spray collector under valve end of nozzle.
(4) Open nozzle tester valve. Operate handle
a few quick strokes and observe popping pressure
indicated on pressure gauge. Popping pressure for
the injectors is 2900 ± 75 psi.
New nozzles and rebuilt nozzles with
new springs are set at 3100 to 3150
psi to compensate for initial set of
new spindle springs.
b. Adjust nozzle to obtain popping pressure as
(1) Remove cap nut (12) from upper end of
nozzle and loosen adjusting screw locknut (9).
(2) While operating handle, turn pressure ad-
justing screw (8) into increase or out to decrease pop-
ping pressure. When pressure is obtained, hold ad-
justing screw and tighten locknut to 60 to 75 foot-
c. Dry the nozzle tip. Operate handle slowly un-
til pressure is approximately 200 psi below popping
Change 1 14-29