N14 Base Engine Troubleshooting and Repair Manual – 006-026   Injector

NOTE: Calibration requires special equipment and
must be done at a Cummins® Authorized Repair Location.

Every 6000 hours, clean and rebuild or replace the injectors.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Disconnect battery cables.
• Remove the crankcase breather tube.
  Refer to Procedure 003-001 (Crankcase Breather (External)) in Section 3.
• Remove the rocker lever cover.
  Refer to Procedure 003-011 (Rocker Lever Cover) in Section 3.
• Remove the compression brakes.
  Refer to Procedure 020-001 (Clutch Switch) in Section 20.
• Remove the rocker lever assemblies (CELECT™
  only).
  Refer to Procedure 003-009 (Rocker Lever Assembly) in Section 3.

NOTE: Excessive crosshead wear can result if the crossheads are
not installed in their original locations. The larger hole on the underside of the crosshead
must be oriented toward the exhaust side of the engine.

Remove the crossheads. Make sure to mark them appropriately, so they can be installed in the same location and orientation during the installation procedure.

Disconnect the injector solenoid leads from the pass-through connector in the rocker lever housing.

Remove the injector hold-down clamp capscrew.

Remove the injector and hold-down clamp.

Use injector puller, Part Number 3823579, to remove the CELECT™ injectors. Insert the pin of the tool into the hole provided in the body of the injector. The hole faces the exhaust side of the engine.

If the injector puller mentioned above is
not available, carefully use a pry bar. Pry upward on the injector against the cylinder head.

NOTE: Mark the position of the push rods as they are removed. Due to wear patterns on the cam follower sockets and adjusting screws, the push rods
must be installed in the same positions from which they are removed.

Loosen the locknut and turn out the adjusting screw on each injector and valve rocker lever.

Some push rods are under compression due to the valves being open. Rotate the crankshaft
clockwise with the accessory drive pulley to relieve the spring tension.

Hold the push rod with one hand to prevent it from falling into the engine. Loosen each adjusting screw and remove the push rod.

NOTE: Do
not remove the links from step timing control injectors.

Rotate the injector and valve rocker levers up on each cylinder.

Remove the crossheads. Mark the position and orientation of the crossheads as they are removed. Due to wear patterns, they
must be installed in the same positions from which they are removed.

Loosen the injector hold-down capscrew and remove the hold-down clamp.

Use Injector Puller/Installer service tool, Part Number 3823579, to remove the injectors.

Take the injectors to a Cummins® Authorized Repair Location for calibration.

CAUTION  To reduce the possibility of damage to the injector sleeves, do not use anything metal to scrape the copper injector sleeves.

Use a clean wooden stick with a clean cloth wrapped around the end to remove all the carbon from the copper injector sleeves in the cylinder head.

Use chip removing unit, Part Number 3823461 or ST-1272-11, to remove the carbon from the top of the piston.

When installing injectors for reuse, new o-rings
must be installed on the injector.

NOTE: The CELECT™ Plus injectors require three different injector o-rings. The traditional black, brown, and black with white dot colors have been changed to red, white, and blue respectively. The coloring is a Teflon® casting; the o-ring material has
not been changed. There is no change in part numbers for these o-rings. The old colors will be present until existing stock is depleted. It is okay to mix the black and the red o-ring, the brown and the white o-ring, or the black with the white dot and blue o-ring.

Top – red

Middle – white

Bottom – blue.

Lubricate the o-rings with lubricating oil just before installation.

CAUTION  To reduce the possibility of injector damage, do not strike the top stop spring cage when installing CELECT™ Plus injectors.

Use the CELECT™ Plus injector puller/installer, Part Number 3823579, to install the injector into the cylinder head injector bore with the injector solenoid valve facing the intake side of the engine.

CAUTION  Do not strike or pry on the solenoid. Otherwise, injector damage will occur.

After partial installation of the injector, take precautions to center the solenoid valve between the valve springs. Avoid contact with the spring coils. If the injector is contacting a valve spring, use a screwdriver to position the injector again.

Continue driving the injector into the bore, use the puller/installer, Part Number 3823579.

If injector puller, Part Number 3823579, is
not available, a screwdriver can be used to install the injector by putting the screwdriver on the injector body at the base of the injector solenoid and striking the screwdriver with a soft mallet. Do
not strike on the injector solenoid or on the top stop spring cage.

CAUTION  The injector must be fully seated before installing the hold-down clamp. The hold-down clamp can not pull the injector into the bore. Engine damage can occur if the injector is not fully seated.

Install the hold-down clamp capscrew.

Take care to route the injector solenoid leads to avoid contact with the valve and injector push tubes.

Connect the injector solenoid leads to the pass-through connector in the rocker housing. Push the lead into the connector until a “snap” is heard.

Check the wire connector to make sure the connector is properly locked in position.

If the wire connector will
not lock into position properly, refer to the CELECT™ Plus Fuel System Troubleshooting and Repair Manual, Bulletin 3666130.

Install the crossheads into their original location to prevent excessive wear.

Install a set of new injectors, use the 8-qt 10-hole cup configuration that was removed from the engine. This will make sure the injectors will
not have any unseen cavitation damage internal to the injector cup at the time of kit installation.

Install three new o-rings over the injector and into the retaining grooves. Do
not twist the o-rings.

Lubricate the o-rings with clean engine oil just before installation.

Check the bores in the cylinder head for burrs or sharp edges that can damage the o-rings. Repair damaged injector bores.

Install new o-rings on the step timing control oil manifold connections.

Align the injector with the oil manifold connections and install the injector into the cylinder head injector bore.

CAUTION  Make sure to place the instrument used to install the injectors on the top cap of the injector, not on the plunger or link. The plungers will be damaged.

Install a 27-mm [1-1/16-in] deep well socket over the top link of the injector. The socket
must rest completely on the top surface of the injector top cap to avoid bending the inner part of the top cap.

Use a clean, blunt instrument to seat the injector in the bore.

A snap will be heard and felt as the injector is seated.

If the injector does
not seat, remove it and check the o-rings for damage. Replace damaged o-rings.

CAUTION  The injector must be fully seated before installing the hold-down clamp. The hold-down clamp can not pull the injector into the bore. Engine damage can occur if the injector is not fully seated.

Install the injector hold-down clamp and capscrew.

Install the crossheads on the valves.

NOTE: The crossheads
must be installed in the same positions from which they were removed.

Rotate the rocker levers down, and install the push rods and push tubes.

NOTE: It is necessary to bar the engine over and install the push rods and push tubes as camshaft position allows.

Make sure the push rods are properly seated in the cam follower sockets.

Turn the adjusting screw for each rocker lever in until it is properly seated in the push rod socket.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Install the rocker lever assemblies CELECT™
  only).
  Refer to Procedure 003-009 (Rocker Lever Assembly) in Section 3.
• Set the valves and injectors.
  Refer to Procedure 003-004 (Overhead Set) in Section 3.
• Install and adjust the compression brakes.
  Refer to Procedure 020-001 (Clutch Switch) in Section 20.
• Install the rocker lever cover.
  Refer to Procedure 003-011 (Rocker Lever Cover) in Section 3.
• Install the crankcase breather tube.
  Refer to Procedure 003-001 (Crankcase Breather (External)) in Section 3.
• Connect the battery cables.