MAIN FUEL FILTER
FUEL SIGHT GAGE
ANTI-VIBRATION RUBBER PADS
MAIN ELECTRICAL SUPPLY
FUEL PUMP MOTOR
CAMSHAFT DRIVE MOTOR
STORAGE BOX (ADAPTERS AND LINKS)
INJECTOR CLAMPING CYLINDER
CLAMPING CONTROL HANDLE
FUEL TANK HEATER
Figure 6-20. Injector Test Stand (Sheet 2 of 2)
6-15. FUEL INJECTOR CLEANING, INSPECTION, AND REPAIR.
Clean all parts ultrasonically to remove all traces of gum, varnish, and carbon.
Check the ball ends of the injector plunger links (2, Figure 6-21) for wear in accordance with Figure 6-22.
Replace the plunger links that show any signs of wear.
Injector Plunger and barrel Inspection.
General. Usually, seizure will be the only true indication of scuffing or scoring. As a result of rocker lever
thrust, bright spots or streaks may appear at the top of the plunger (3, Figure 6-21), and on the opposite
side at the bottom of the plunger. Provided seizure or scoring is not evident, these spots are normal and
the plunger should be reused. Narrow streaks running from the top to the bottom of the plunger are usually
caused by thickness variations in the penetrant treatment used to prevent corrosion. Again, unless seizure
or scoring is evident, reuse the plunger.
Check the plunger (3) surface for signs of seizure, scoring, and wear ridges. The surface should show no
signs of wear or scoring.
Check the plunger (3) spring seat for wear or cracks. The spring seat should show no cracks or signs of
Inspect the bore of the barrel (15) using a four power magnifying glass. The bore should show no signs of
wear or scoring.
Using a four power magnifying glass, inspect the check ball seat in the barrel (15) for burrs and wear.
The seat should show no signs of burrs or wear.
See Figure 6-23. Install a check ball (1) in the barrel (2), and check the depth of the check ball seat by
measuring A. Measurement of A must be 0.030 to 0.055 inch (0.76 to 1.40 mm). Replace the check ball
(1) or the barrel (2), or both, as necessary to achieve the required depth.
Replace both the plunger (3, Figure 6-21) and barrel (15) as a matched set for any defects found in steps
(2) through (5), above.
Inspect the cup (16, Figure 6-21) tip and spray holes with a four power magnifying glass. There should be
no signs of abrasive wear, corrosion, or enlarged or elongated spray holes.Replace
Check the cup (16) spray pattern using injector cup spray tester 3376350 (Figure 6-19). Replace cups that
have irregular spray patterns.
Using spring tester MIL-T-43560, check the load required to compress the spring (4, Figure 6-21) to a length of
2.40 inches (61.0 mm). Replace the spring if the required load is less than 129.00 pounds (58.51 kg), or more
than 149.75 pounds (67.93 kg).
Inspect the injector retainer (12) for nicks or burrs which could prevent proper seating with the sealing ring (1).