3406E and 3456 Industrial Engines – Electronic Unit Injectors

Remove & Install Electronic Unit Injectors

Start By:

a. remove rocker shaft assembly

Fluid Spillage Containment

Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to “Tools And Shop Products Guide”, NENG2500 for tools and supplies suitable to collect and contain fluids in Caterpillar machines. Dispose of fluids according to local regulations and mandates.

1. Loosen the two nuts and remove connector (1) from electronic unit injector (3). Set the wires to electronic unit injector aside.

2. Mark bridge assemblies (2) for purpose of reassembly. Remove two bridge assemblies (2).

3. Remove bolt (4) from spacer (5) and clamp (6) (spacer (5) and clamp (6) not shown in the above photograph) holding electronic unit injector (3) to the cylinder head. For assembly purposes, the torque for bolt (4) is 47 ± 9 N·m (35 ± 7 lb ft).

4. Use Tool (A) to pry beneath the base and free electronic unit injector (3).

5. Lift electronic unit injector (3), spacer (5) and clamp (6) from the cylinder head.

6. Check the condition of O-ring seals (7) and (8). Use new parts for replacement if the O-ring seals appear worn or damaged.

NOTE: Lubricate O-ring seals (7) and (8) with clean engine oil before installing the electronic unit injector into the cylinder head.

7. Install the electronic unit injectors in the reverse order of removal.

End By:

a. install rocker shaft assembly