Opening Pressure
- Pump pressure up slowly to note opening pressure. If not within 1705-1850 psi (120-130 kg/cm2 ) for I-Mark models or 1495-1635 psi (105-115 kg/cm2 ) on P'UP models, clean or replace injector.
- Check injector nozzles for leakage by installing in tester and maintaining 284 psi (20 kg/cm2 ) pressure. If any leakage is evident, injector must be cleaned or replaced.
- When assembling injectors, use centering tool (J-33178) to install nozzle in center of nozzle body holder. See Fig 3 . Tighten retaining nut to 65 ft. lbs. (88 N.m).
- After tightening retaining nut, draw out centering tool. If it cannot be drawn out easily, nozzle body is not fitted properly. Loosen retaining nut and tighten properly. Adjust nozzle opening pressure after assembly.
- I-Mark injectors use adjustment shims to change opening pressures. Shims are available in sizes from .0197" (.5 mm) to .0394" (1 mm) in .0016" (.04 mm) increments. Every increase of .0016" (.04 mm) will increase opening pressure by 68 psi (4.8 kg/cm2 ).
- In addition, .002" (.05 mm) shims are available for I-Mark models for fine tuning adjustments. Opening pressure will increase 85 psi (6 kg/cm2 ) for every .002" (.05 mm) shim added. Injectors on P'UP models use an adjustment screw to change opening pressure.