BOLT-LOCKING 5P8081 - Caterpillar

3408E (7PR),
3412E (4CR) Industrial EnginesReference: Special Instruction, REHS0116, "Removal And Installation Of Hydraulic Electronic Unit Injectors (HEUI)"These engines are equipped with HEUI fuel systems. In order to avoid damaging the unit injectors and subsequent possible major engine damage, use the following procedure when installing HEUI injectors.
Installation Of HEUI Injectors
(1) O-ring seal. (2) O-ring seal. (3) Tapered seat.1. Clean the carbon from:* The tapered Seat (3) on the injector.
If you are cleaning the tapered Seat (3) on the injector with a wire brush, do not let the wire brush contact the tip of the injector. A wire brush may damage the tip of the injector.
* The tapered seat in the injector sleeve.2. Install new O-ring seals (1) and (2).3. Lubricate the O-ring seals (1) and (2), and the injector sleeve bore lightly with clean engine oil. Install the HEUI Injector in its original location in the injector sleeve.
View of the wire assembly. (4) Cap and nut assemblies. (5) Wire assembly.4. Connect the wire assembly (5). Install the cap assembly and nuts (4). Tighten the nuts to a torque of 1.70 0.25 N m (15 3 in lb).
(6) View of the clamp. (7) Bolt. (8) O-ring seal.5. Position the clamp (6) and tighten the bolt (7) to 47 9 N m (35 7 lb ft).
(9) View of the O-ring seals installed in the jumper tube. (10) O-ring seals installed in the rocker arm base.6. Install the O-ring seal (8) and the O-ring seals (9) in the jumper tube and in the rocker arm base (10).
(11) View of the jumper tube. (12) Bolts (one bolt hidden in this view). (13) Adapter. (14) Socket head cap screws.7. Place the jumper tube (11) and adapter (13) in position.
If the adapter was previously installed on the HEUI injector, loosen the socket head cap screws. Failure to loosen the socket head cap screws before continuing with Step 8 can result in HEUI injector failure.
8. Install the socket head cap screws (14) and four bolts (12). The objective at this point in the procedure is to bring all the mating faces into complete contact and alignment before starting the final torque procedure.
Failure to use the correct torqueing procedure may cause injector damage and subsequent major engine damage.
Torquing Procedure
Tighten the two socket head cap screws (3) and the two horizontal bolts (1) and two vertical bolts (2) finger tight to bring the mating surfaces together and into alignment.
Socket head cap screws (3).
(1) Two bolts (horizontal). (2) Two bolts (vertical).1. Tighten the socket head cap screws (3) to an initial torque of 1 0.2 N m (10 2 lb in).2.