TM 5-3805-258-24-1
F U E L S Y S T E M
T E S T I N G A N D A D J U S T I N G
When fuel injection nozzles are tested, be
sure to wear eye protection. Test fluid
comes from the orifices in the nozzle tip with
high pressure. The test fluid 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.
N O Z Z L E R E A D Y F O R T E S T
E. Gauge protector valve. H. On-off valve. K. Pump isola-
tor valve.
CAUTION
Put a shop towel around the upper part of
the nozzle to take in any fluid leakage.
3. Close on-off valve (H). Open pump isolator
valve (K).
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 not within specifications,
do not use the fuel injection nozzle again.
VALVE OPENING PRESSURE (VOP) SPECIFICATIONS
8300 to 16200 kPa
(1200 to 2350 psi)
Il. Flush the Nozzle
1. Close gauge protector valve (E). Close on-off
valve (H). Open pump isolator valve (G).
NOTE: Make sure nozzle extends inside and below
the top of FT1384 Extension (F).
2. Operate the pump rapidly for three full strokes.
III. Tip Leakage Test
1.
2.
Remove all fluid from the nozzle tip and body
with a clean cloth.
Put a clean cloth around the body of the nozzle to
take in any leakage from the bleed screw hole
and prevent any fuel leakage to drain down to
the tip of the nozzle.
N O Z Z L E R E A D Y F O R T E S T
E. Gauge protector valve. H. On-off valve. K. Pump isola-
tor valve.
3.
4.
Open gauge protector valve (E). Close on-off
valve (H). Open pump isolator valve (K).
Make and hold for 15 seconds a pressure of 1380
kPa (200 psi) less than the opening pressure
measured in VOP Test I and make a note of the
number of drops that fall.
TIP LEAKAGE SPECIFICATION
No more than 5 drops can fall in 15 seconds.
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