TM 5-3895-359-14&P
TROUBLE SHOOTING CHARTS (Needle Valve Injectors)
Chart 2
INSUFFICIENT INJECTOR HOLDING TIME
Probable Cause
1. POOR BUSHING TO BODY FIT
8. WORN OR BROKEN VALVE SPRING
2. INJECTOR NUT NOT TIGHTENED
9. WORN OR DAMAGED VALVE
TO SPECIFIED TORQUE
SPRING SEAT
3. EXCESSIVE PLUNGER TO BUSHING
10. DEFECTIVE SEAL RINGS
CLEARANCE
4. CRACKED SPRAY TIP
11. BODY PLUG LEAKS
5. WORN OR ERODED NEEDLE VALVE
12. FILTER GASKETS LEAK
6. WORN OR ERODED NEEDLE VALVE
13. POOR SEALING SURFACES ON
SEAT IN SPRAY TIP
FUEL FITTINGS
7. WORN OR BROKEN NEEDLE VALVE
14. DIRT OR FOREIGN MATERIAL
QUILL
IN INJECTOR
SUGGESTED REMEDY
1. Lap the injector body.
10. Replace the seal rings.
2. Tighten the injector nut to 75-85 lb-ft (102-115
11. Install new body plugs.
12. Replace the filter cap gaskets and tighten the filter
3. Replace the plunger and bushing.
caps to 65-75 Ib-ft (88-102 Nm) torque.
4, 5, 6 and 7. Replace the needle valve and spray tip
13. Clean up the sealing surfaces or replace the filter
assembly.
caps, if necessary. Replace the filter if a cap is
replaced.
8. Replace the valve spring.
14. Disassemble the injector and clean all of the parts.
9. Replace the valve spring seat.
10-3-60
