Caterpillar 3406 B/C
REMOVAL & INSTALLATION OF FUEL INJECTION PUMPS

•Removal of Fuel Injection Pump

NOTICE: Before any parts are removed from the fuel injection pump housing, thoroughly clean all dirt from the housing. Dirt that gets inside the pump housing will cause much damage.
NOTE: The fuel rack must be in the zero (center) position before the fuel injection pumps can be removed or installed. Follow Steps 1 through 5.

1. Remove plug (1) and cover (2) from the fuel injection pump housing.
2. Install the 6V4186 Timing Pin (3) in the top of the fuel injection pump housing.  Make sure timing pin (3) engages in the slot of the fuel rack as shown.
3. Install bracket assembly (4) on the fuel injection pump housing.  Make sure the lever of the bracket assembly is engaged in the slot of the fuel rack.
4. Install the 1U5426 Compressor Assembly (5) all the way into the 8T9198 Bracket Assembly (4) to compress the spring.
5. Tighten the collet on bracket assembly (4) to hold compressor assembly (5).  Spring force now holds the fuel rack against timing pin (3) in the zero position.
6. Remove the fuel injection line from the pump to be removed and also the fuel injection lines on each side of the pump to be removed

WARNING:
There is spring force on the fuel injection pup plunger and barrel assembly.  Removal of retainer bussing (8) without the 6V7050 Compressor Group correctly installed can cause bodily injury.

7. Use 8T5287 Wrench (6) to loosen bushing (8) one-quarter turn.  Do not remove the bushing at this time.
8. Install 6V7050 Compressor Group (7) on the pump housing over 8T5287 Wrench (6).  Lower the screw in the compressor ram to the fuel line seat before the nut is tightened to hold the compressor group in position.  This centers the compressor group.
9. Use 8T5287 Wrench (6) to loosen retainer bushing (8) until it is out of the threads.  Slowly raise the compressor tool handle to release the spring force.
10. Remove the 6V7050 Compressor Group and the 8T5287 Wrench.  Install 8S2244 Extractor (9) on the injection pump threads.  Carefully pull the pump straight up and out of the pump housing bore.  Remove the spacer form the pump housing bore.  Be careful when an injection pump is disassembled.  Do not damage the surface on the plunger.  The plunger and barrel are made as a set.  Do not put the plunger of one pump in the barrel of another pump.  If one part is worn, install a complete new pump assembly.  Be careful when the plunger is put into the bore of the fuel injection pump housing, keep the parts together so they can be installed in the same location in the housing.



•Installation of Fuel Injection Pump
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NOTICE: The fuel rack MUST BE IN THE CENTER POSITION before the correct installation of an injection pump is possible

1. Put the fuel rack in the center position.  See Removal of Fuel Injection Pumps for this procedure.
2. Put 8S2244 Extractor (1) on the threads of the fuel injection pump.
3. Make sure the lifter for the pump to be installed is at the bottom of its travel (cam lobe is at its lowest point).
4. Put the groove in barrel (2) in alignment with the slot (grove) in gear segment (3).
5. Be sure the spacer is in position in the pump-housing bore.
6. Carefully install the pump straight down into the pump-housing bore.

NOTE:
The slot (groove) in gear segment (3) must be in alignment with pin (4) in the side of the lifter and the grove in barrel (2) must be in alignment with dowel (5) in the housing bore.

7. Remove the 8S2244 Extractor Put the O-ring seal, retainer bushing (9) and 8T5387 wrench (7) in position on the top of the injection pump.  Install 6V7050 Compressor Group (8).
8. Slowly move the handle of the 6V7050 Compressor Group down to push the injection pump into the bore.

NOTICE:
The handle of the 6V7050 Compressor Group must move smoothly down to the lock position.  Do not force the handle if it stops.  If the handle does not move smoothly down to the lock position, raise the handle, remove the 6V7050 Compressor Group, and repeat Steps 3 through 8.

9. Put the O-ring seal in position in the pump-housing bore.  Use the 8T5287 Wrench to install the retainer bushing.
10. Remove the 6V7050 Compressor Group.  Tighten the retainer bushing to 230 +- 15 N*m (170 +- 11 lb ft).

NOTICE:
The bushing must be tightened to the correct torque.  Damage to the housing will be the result if the bushing is to tight.  If the bushing is not tight enough, the pump will have leakage.

11. Install the fuel injection lines to the pump and tighten to 40 +- 7 N*m (30+_ 5ib ft.).  See Fuel Injection lines in this section for more information.

WARNING:
Be sure the fuel injection line clamps are instilled in the correct locations. Incorrectly installed clamps may allow the fuel injection lines to vibrate and become damaged. The damaged lines may leak and cause a fire.

The following steps can be used to insure correct installation and operation of any number of individual replacement pumps on most truck engines.

12. Remove or activate the shutoff solenoid if it is installed in the rack actuator housing.

NOTE: The manual shutoff override lever can be used to move the shutoff solenoid out of the way so the fuel rack can be moved.

NOTE:
To check the installation of a replacement pump, it is necessary to have full rack travel in both directions.  The actual zero location of the timing pin and rack are not used to check the installation of replacement pumps.

13. Remove the compressor and bracket assembly (10) from the fuel injection pump housing.
14. Raise the timing pin and move the rack to the full load position.  Use finger pressure to be sure the rack is at full rack travel (beyond full load position).
15. If the fuel injection pump installation is correct, when the timing pin is lowered it will be on the rack as shown in illustration 1.
16. If the fuel injection pump installation is NOT correct, the timing pin position will be approximately 1.91 mm (.075 in) toward the slot for each tooth position out of alignment (see illustration 2).  This will reduce fuel rack travel, even though it may not affect the rack setting, because of additional rack travel at static conditions.
17. Raise the timing pin and move the rack to the no load (fuel off) position.
18. If the fuel injection pump installation is correct, when the timing pin is lowered it will be in the timing slot, less than 1.91 mm (.075 in) from the rear face of the slot as shown in illustration 3.