Nozzle Cleaning
- Disassemble injector nozzle. If nozzle needle is damaged, fused, seized or discolored, replace entire nozzle assembly. Check all other parts for excessive wear or damage. Replace as needed.
- Scrape off carbon deposits with a piece of wood and clean each part in cleaning solvent. After cleaning, keep parts immersed in light oil. Be sure to remove all deposits from components. Nozzle must be replaced if needle seats are worn or damaged.
- Hold nozzle vertically and insert needle. Lift needle about 1/3 way out of nozzle and release. Needle should slide smoothly back into place. Repeat this procedure several times, rotating needle slightly each time. If needle does not slide smoothly, replace nozzle body and needle.
- 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 can't be drawn out easily, nozzle body has not been 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.