Fuel Injector: Service and Repair

Removing And Installing Injection Valves - Engine Installed

WARNING:
- Observe the general safety instructions when working on the fuel system and when handling petrol and other fuels.
- Always disconnect the battery prior to working on the fuel system.

INFORMATION: When using fuel, a warning sign should be attached or mounted on the vehicle in a clearly visible position.

CAUTION: Coolant is hazardous to the health and irritates the skin. Danger of scalding when the engine is hot. Do not begin working until the engine has cooled down.

- When handling coolant, wear protective gloves and goggles.
- In case of contact with the skin or eyes, wash immediately with plenty of water.

CAUTION: To avoid damage to the hoses, lines and engine, the engine must only be lowered by approx. 30 mm - 40 mm.

1. Disconnect the battery.
2. Remove air cleaner housing.

Removing injection valves of cylinder bank 1 - 3
1. Remove the secondary air pump. To do this, remove the cable plug at the side, unscrew the M6 hexagon nut at the top, unscrew both M6 hexagon-head bolts at the bottom and remove the connecting cable from the cable retainer. Pull off connecting hose to the secondary air pump and remove the pump from the engine compartment.

2. Unscrew cap of the coolant expansion tank and drain the coolant. To do so, undo the spring band clamp of the coolant hose at the housing of the coolant temperature regulator -arrow- and pull off the hose. Collect the draining coolant.
3. Disconnect plug connection of the fuel line -1-. Unclip fuel line at the plastic clip of the coolant expansion tank. Collect emerging fuel with a cloth.
4. Separate plug connection of -2- of the tank vent line to the tank vent.
5. Open spring band clamps of coolant hoses -3 and 4- on the coolant expansion tank using a mounting tool for spring band clamps, pull off the coolant hoses and set them aside.
6. Remove cable plug of the coolant level sensor -5-.
7. Remove cable plug of the electrical switch-over valve -6- above the generator.

INFORMATION: In order to avoid damage to lines or hoses, the engine must not be lowered more than 40 mm.

8. Lower the engine by 30 - 40 mm. To do this, support the engine with a jack and unscrew the two collar nuts (a/f 18) of the engine mounts. Pay attention to hose and cable connections.

9. Unclip the wiring harness of the injection valves from the 3 cable retainers on the fuel collection pipe -2- and set aside. Unscrew the two M6 hexagon-head bolts of the fuel collection pipe -1-.
10. Remove cable plugs of the injection valves by pressing in the wire clips and pulling off the cable plugs.
11. Pull the fuel collection pipe complete with the injection valves out of the intake pipe and place it on the cylinder head.

INFORMATION: Collect emerging fuel with a cloth.

12. Pull the retainers off the injection valves -A- and pull the injection valves out of the fuel collection pipe -B-. Make sure that all O-rings are present on the injection valves. Collect emerging fuel with a cloth.

Installing injection valves of cylinder bank 1 - 3

INFORMATION: Replace O-rings of the injection valves.

1. Replace O-rings of the injection valves and press the valves into the fuel collection pipe -A-. The O-rings can be sprayed, e.g. with silicone spray, for easier assembly. Fit the retainers -B- of the injection valves correctly (they must snap into place).
2. Push the fuel collection pipe complete with injection valves into the intake pipe and insert the two M6 x 12 hexagon-head bolts of the fuel collection pipe into the intake pipe. Make sure that the loose wiring harness is not trapped.
3. Tighten both M6 x 12 hexagon-head bolts with the correct tightening torque.

Tightening torque 10 Nm (7.5 ftlb.)

4. Correctly route the wiring harness of the injection valves and clip it into the cable retainers on the fuel collection pipe -2-.

5. Push cable plugs onto the injection valves by pushing on the cable plugs until they audibly engage.
6. Push on cable plug of the switch-over valve above the generator -6-.
7. Push on cable plug of the coolant level sensor -5-.
8. Push coolant hoses -3 and 4- onto the connections on the coolant expansion tank and fasten them in place with spring band clamps using a mounting tool for spring band clamps.
9. Fit plug connection of the tank vent line to the tank vent -2- by pressing the rapid-action coupling onto the connection line to the tank valve.
10. Fit plug connection of the fuel line by pressing the rapid-action coupling -1- onto the line. Clip in fuel line at the plastic clip of the coolant expansion tank.
11. Raise the engine again with the jack and then tighten the two collar nuts (a/f 18) on the engine mounts with the correct torque.

Tightening torque 85 Nm (63 ftlb.)

12. Install the secondary air pump. To do so, connect the cable plugs, tighten the upper hexagon nut, tighten the two M6 hexagon-head bolts at the bottom and insert the cable into the plastic clip. Push connecting hose onto the connection.

Tightening torque of M6 screw connections 10 Nm (7.5 ftlb.)

13. Install air cleaner housing
14. Top up coolant and bleed cooling system.
15. Connect the battery.

Removing injection valves of cylinder bank 4 - 6

INFORMATION: In order to avoid damage to lines or hoses, the engine must not be lowered more than 40 mm.

1. Lower the engine by 30 - 40 mm. To do this, support the engine with a jack and unscrew the two collar nuts (a/f 18) of the engine mounts. Pay attention to hose and cable connections.

2. Unclip the wiring harness of the injection valves from the 3 cable retainers on the fuel collection pipe -1- and set aside. Remove both cable plugs of the oil pressure sensor -2-.
3. Unscrew the two M6 hexagon-head bolts of the fuel collection pipe.
4. Remove cable plugs of the injection valves by pressing in the wire clips and pulling off the cable plugs.
5. Pull the fuel collection pipe complete with the injection valves out of the cylinder head and place it on the cylinder head.

INFORMATION: Collect emerging fuel with a cloth.

6. Pull the retainers off the injection valves -A- and pull the injection valves out of the fuel collection pipe -B-. Make sure that all O-rings are present on the injection valves. Collect emerging fuel with a cloth.

Installing injection valves of cylinder bank 4 - 6

INFORMATION: Replace O-rings of the injection valves.

4. Route the wiring harness of the injection valves and clip it into the cable retainers on the fuel collection pipe -1-. Push on the two cable plugs of the oil pressure sensor -2-.
5. Push cable plugs onto the injection valves by pushing on the cable plugs until they audibly engage.
6. Raise the engine again with the jack and then tighten the two collar nuts (a/f 18) on the engine mounts with the correct torque.

Tightening torque 85 Nm (63 ftlb.)

7. Install air cleaner housing
8. Connect the battery.