TM 5-3825-226-24
NOZZLE POSITION FOR RETURN LEAKAGE TEST
1. Fuel Injection nozzle. 0. 5P4244 Adapter. R.
FT1384 Extension. S. 8S2270 Fuel Collector.
5. Close on-off valve (F). Open pump isolator valve
(G).
6. Open gauge protector valve (E) and operate the
tester slowly until the pressure is at 1400 to 1600 psi
(9630 to 11 045 kPa).
7. Look at the leakage from the return at the top
(pressure screw end) of the fuel injection nozzle.
RETURN LEAKAGE SPECIFICATION
Minimum
Maximum
After the first
drop falls:
No
Minimum
No
Maximum
II. Valve Opening Pressure Test (VOP)
1.
Loosen nut (5) and turn nozzle tip down so that
it extends into FT1384 Extension (R) as shown.
2.
Tighten nut (5) to 5P4244 Adapter (Q). Nut (5)
can be tightened by hand if 1H1023 O-ring Seal
(6) is not damaged.
NOZZLE CONNECTED TO 5P4150 NOZZLE TESTER
WARNING
When fuel injection nozzles are tested, be
sure to wear eye protection. Fuel comes from
the orifices in the nozzle tip with high
pressure. The fuel can pierce (go thru) the
skin and cause serious injury to the operator.
Keep the tip of the nozzle pointed away from
the operator and into the 8S2270 Fuel
Collector and FT1384 Extension.
NOZZLE READY FOR TEST
E. Gauge protector valve. F. On-off valve. G.
Pump Isolator valve.
CAUTION
Put a shop towel around the top of the nozzle
(pressure screw end) to take in any fuel
leakage.
3.
Close on-off valve (F). Open pump isolator
valve (G).
4.
Open gauge protector valve (E). Operate the
pump to make a slow increase in pressure until
the valve in the fuel injection nozzle just starts
to open. Read the maximum gauge pressure at
the instant fluid flows from the tip.
NOTE: It is possible for the pressure reading of the
gauge to go down fast if the valve makes a noise
(chatters) when it opens. It is also possible for the
pressure reading of the gauge to be almost constant
when the valve in the fuel injection nozzle opens.
NOTE: The valve in the fuel injection nozzle can be
good and still not make a noise (chatter), or not have a
very fine vapor (spray) from the orifices in the tip of the
fuel injection nozzle during Step 4.
If the opening pressure is less than 1500 psi 10300
kPa), do not use the fuel injection nozzle again.
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