TM 9-2320-272-24-4
5-21. INJECTOR SPRAY PATTERN TEST
THIS TASK COVERS:
b. Testing Spray Pattern
a. Setting Up Spray Pattern Tester
INITIAL SETUP:
REFERENCES (TM)
APPLICABLE MODELS
TM 9-2320-272-24P
M939/A1
EQUIPMENT CONDITION
SPECIAL TOOLS
Fuel injectors removed (para. 4-32).
Fuel injection tester (Appendix E, Item 49)
Spray angle tester (Appendix E, Item 138)
GENERAL SAFETY INSTRUCTIONS
TOOLS
Whenever fuel is forced from injector spray holes,
keep hands away from spray stream.
General mechanic's tool kit (Appendix E, Item 1)
a. Setting Up Spray Pattern Tester
NOTE
Any source of 22 psi (152 kPa) constant fuel pressure will operate
spray pattern tester.
1.
Locate spray pattern tester near or on injector test stand.
2.
Attach inlet hose (2) to adapter (8) from injector test stand.
3.
Attach drain hose (4) to adapter base (5) and place loose end in test stand drain area.
4.
Remove plunger (10) and spring (11) from injector (12) and store in safe place.
5.
Remove screen retaining ring (15) and inlet fuel screen (14) from injector test stand.
6.
Place injector (12) in adapter (8).
7.
Install knurled plug (6) in adapter (8) drain opening.
8.
Place injector (12) in spray pattern tester and tighten inlet hose connector (3).
9.
Install injector (12) in spray patter tester holddown bracket (9) with knurled knob (1).
Install target ring (7) marked 8-.007 x 17o on spray pattern tester.
10.
b. Testing Spray Pattern
WARNING
Keep hands away from spray stream when fuel is forced from injector
spray holes. Failure to do this may result in injury to personnel.
1.
Apply 22 psi (152 kPa) pressure to injector test stand.
NOTE
Each spray stream must hit a window in the target ring.
Shift target ring (7) so one spray stream hits on No. 1 or index window. If spray stream is off 2o of
2.
window, replace cup (para. 5-19).
3.
Loosen knurled knob (1) on holddown bracket (9).
4.
Remove injector (12) from spray pattern tester.
5.
Remove knurled plug (6) and injector (12) from adapter (8).
6.
Install spring (11) and plunger (10) in injector (12).
7.
Install inlet fuel screen (14) over injector orifice (13) with screen retaining ring (15).
5-140
