Fuel Injectors & Pumps

Section 3.1 Series 50/60 Unit Injector Inspection/Removal

Section 3.1
Series 50/60 Unit Injector Inspection/Removal

To determine if the unit injector is not functioning properly and needs to be replaced, follow this procedure:‪

  1. Drain fuel system and remove EUI.
  2. Clean EUI (See current Series 60 service manual (6SE483) or Series 50 service manual (6SE50) for proper procedure).
  3. Inspect EUI for leaks, turned O-rings, broken injector follower spring, seized injector, cracked body, loose valve stop screws, blown pressure plug, plugged or blown spray nozzle, or broken terminal screws. See Section 6.
  4. The only serviceable items are the Injector Follower Spring and O-rings.
  5. Replace and install new or remanufactured injector if required.

Follow the service manual procedures to remove the unit injector:‪

  1. Clean the valve rocker cover around its seat on the head, and in the attaching bolt recesses.
  2. Drain the cylinder head fuel gallery by removing the inlet and outlet lines from the fittings at the rear of the cylinder head. Use caution and blow low pressure compressed air 276 kPa (40 psi) maximum, into the inlet fitting for 20 to 30 seconds or until all of the fuel is purged from the cylinder head.
  3. Remove the two rocker shaft through-bolts and one nut for each rocker shaft assembly, and lift the rocker shaft assembly off the engine.
  4. Remove unit injector terminals from solenoid, or if N3 injector, disconnect the wiring connector.
  5. Lift the injector from its seat in the cylinder head by inserting a pry bar under the injector body.

Note: For current information on removal and installation, refer to the MBE 900 service manual (6SE414).


Unit Fuel Injectors and Unit Pumps Technician's Guide - 7SE500
Generated on 10-13-2008

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