1998 NISSAN PICK-UP Repair Manual

ADJUSTMENT
Adjust adjusting bolt on the normal operating side so that the
starting injection quantity is as specified.
Refer to ``Injection Pump Calibration Standard'' in SDS for the
starting injection quantity.
MEF455B
INJECTION PUMPTD
Start Q Adjustment Lever (Cont'd)
EC-185

Removal and Installation
1. Remove injection tube assembly.
2. Remove spill tube assembly.
To prevent spill tube from breaking, remove it by gripping
nozzle holder.
3. Remove injection nozzle assembly using deep socket
wrench.
4. Install injection nozzle in the reverse order of removal.
Injection nozzle to cylinder head:
:54-64Nzm (5.5 - 6.5 kg-m, 40 - 47 ft-lb)
Spill tube nut:
:29-39Nzm (3.0 - 4.0 kg-m, 22 - 29 ft-lb)
Injection tube flare nut:
:20-25Nzm (2.0 - 2.5 kg-m, 14 - 18 ft-lb)
a. Nozzle gaskets should always be replaced.
b. To prevent spill tube from breaking later, spill tube nuts
should be tightened gradually in sequence.
5. Bleed air from fuel system.
Refer to ``Bleeding Fuel System'', EC-191.
Disassembly
1. Loosen inlet connector while keeping nozzle top from turning.
2. Arrange all disassembled parts in order shown at left.
DEM025
DEM026
SEF785
SEF425F
INJECTION NOZZLETD
EC-186

Inspection
Thoroughly clean all disassembled parts with fresh kerosene or
solvent.
lIf nozzle needle is damaged or fused, replace nozzle assem-
bly with a new one.
lIf end of nozzle needle is seized or excessively discolored,
replace nozzle assembly.
lCheck nozzle body and distance piece for proper contact. If
excessively worn or damaged, replace nozzle assembly or
nozzle holder assembly.
lCheck spacer and nozzle holder for proper contact. If exces-
sively worn or damaged, replace spacer or nozzle holder.
lCheck nozzle spring for excessive wear or damage. If exces-
sively worn or damaged, replace it with a new spring.
Cleaning
a. Do not touch the nozzle mating surface with your fin-
gers.
b. To wash the nozzles, use a wooden stick and brass
brush with clean diesel fuel.
1. Clean nozzle assembly using the Nozzle Cleaning Kit.
2. Portions which should be cleaned are indicated in the left
figure.
3. Remove any carbon from exterior of nozzle body (except
wrapping angle portion) by using Tool.
SEF828
SEF426F
SEF830
INJECTION NOZZLETD
EC-187

4. Clean fuel sump of nozzle body using Tool.
5. Clean nozzle seat by using Tool.
This job should be performed with extra precautions, since
efficiency of nozzle depends greatly on a good nozzle seat.
6. Clean spray hole of nozzle body by using Tool.
To prevent spray hole from canting, always clean it by start-
ing with inner side and working towards outside.
7. Decarbon nozzle needle tip by using Tool.
8. Check needle for proper position.
(1) Pull needle about halfway out from body and then release it.
(2) Needle should sink into body very smoothly from just its own
weight.
(3) Repeat this test and rotate needle slightly each time.
If needle fails to sink smoothly from any position, replace
both needle and body as a unit.
SEF831-B
SEF832-B
SEF833
SEF834
SEF835
INJECTION NOZZLETD
Cleaning (Cont'd)
EC-188

Assembly
Assemble in the reverse order of disassembly.
Inlet connector to nozzle holder:
:29-49Nzm (3.0 - 5.0 kg-m, 22 - 36 ft-lb)
Test and Adjustment
WARNING:
When using nozzle tester, be careful not to allow diesel fuel
sprayed from nozzle to contact your hand or body, and
make sure your eyes are properly protected with goggles.
INJECTION PRESSURE TEST
1. Install nozzle to injection nozzle tester and bleed air from
flare nut.
2. Pump the tester handle slowly (one time per second) and
watch the pressure gauge.
3. Read the pressure gauge when the injection pressure just
starts dropping.
Initial injection pressure:
Used 9,807 - 10,297 kPa
(98.1 - 103.0 bar, 100 - 105 kg/cm
2,
1,422 - 1,493 psi)
New 10,297 - 11,278 kPa
(103.0 - 112.8 bar, 105 - 115 kg/cm
2,
1,493 - 1,635 psi)
Always check initial injection pressure using a new nozzle.
SEF967
EF791A
SEF672A
INJECTION NOZZLETD
EC-189

4. To adjust injection pressure, change adjusting shims.
a. Increasing the thickness of adjusting shims increases
initial injection pressure. Decreasing thickness reduces
initial pressure.
b. A shim thickness of 0.04 mm (0.0016 in) corresponds
approximately to a difference of 471 kPa (4.71 bar, 4.8
kg/cm
2, 68 psi) in initial injection pressure.
Refer to ``Injection Nozzle'' in SDS for adjusting shims,
EC-233.
LEAKAGE TEST
1. Maintain the pressure at about 981 to 1,961 kPa (9.8 to 19.6
bar, 10 to 20 kg/cm2, 142 to 284 psi) below initial injection
pressure.
2. Check that there is no dripping from the nozzle tip or around
the body.
3. If there is leakage, clean, overhaul injection nozzle or replace
it.
SPRAY PATTERN TEST
1. Check spray pattern by pumping tester handle one full stroke
per second.
a. If main spray angle is within 30 degrees as shown, injec-
tion nozzle is good.
b. It is still normal even if a thin stream of spray deviates
from main spray (pattern B).
2. If injection nozzle is not normal, adjust or clean injection
nozzle or replace it.
SEF427F
SEF674A
SEF079S
INJECTION NOZZLETD
Test and Adjustment (Cont'd)
EC-190

Bleeding Fuel System
Air should be bled out of fuel system when injection pump
is removed or fuel system is repaired.
Protect pump and engine mounts from fuel splash with rags.
If engine will not start after bleeding air, loosen injection
tubes at nozzle side and crank engine until fuel overflows
from injection tube. Tighten injection tube flare nuts.
If the engine does not operate smoothly after it has started, race
it two or three times.
CAUTION:
Wipe up any fuel discharged while bleeding air during each
step.
lStep 1: Fuel filter and injection pump bleeding
1. Loosen air bleeder screw to injection pump.
2. Move fuel filter priming pump up and down until no further air
comes out of air bleeder screw.
3. Tighten air bleeder screw.
lStep 2: Fuel injection tube and spill tube air bleeding
1. Loosen injection tube nuts on nozzle holder side.
2. Move the priming pump up and down until no further air
comes out of the injection tube nuts.
3. Tighten the injection tube nuts.
:20-25Nzm (2.0 - 2.5 kg-m, 14 - 18 ft-lb)
SEF083K
DEF015
SEF307K
FUEL SYSTEM CHECKTD
EC-191

Bleeding Fuel Filter
1. Move the priming pump up and down to bleed air from the
fuel filter.
2. When air is completely bled from the fuel pump, priming
pump operation becomes noticeably heavy. Stop pump
operation.
Checking Priming Pump
Before checking priming pump, make sure that fuel filter is
filled with fuel.
1. Disconnect fuel return hose.
Place a suitable container beneath hose end.
2. Pump priming pump and check that the fuel overflows from
the hose end. If not, replace priming pump.
Checking Fuel Filter Switch
1. Remove the connector from filter and fuel filter switch.
2. Turn the key switch ``ON''. Lift the float to ensure that the
warning lamp turns on.
Fuel filter switch tightening torque:
: 3.9 - 5.9 Nzm (0.4 - 0.6 kg-m, 35 - 52 in-lb)
Discard the old O-ring and replace it with a new one.
DEF017
SEF122U
FUEL SYSTEM CHECKTD
EC-192