Disassembling the Engine
Disassembling the engine
Information
Tools and materials
Loosen or tighten all threaded connections according to instructions in the document.
Overview of special tools
Special tools for engine disassembly
1- Retaining device 9778 with piston receiving element with a diameter of 97 mm.
2- Piston receiving element 9778/1, diameter: 102 mm.
3- Funnel 9784 or funnel 9784/2 for piston assembly, diameter: 97 mm or 102 mm.
4- Piston assembly aid 9787, diameter: 97 mm or piston assembly aid 9787/1, diameter: 102 mm.
5- Handle for assembly aid 9598.
6- Disassembly tool 9764 for piston-pin circlips.
7- Disassembly tool 9777 and assembly tool for piston pins.
8- Assembly tool 9776 for piston-pin circlips.
9- Centering mandrel 9782 for connecting rods and pistons.
10- Assembly aid 9783 for pressing out pistons (cylinders 1-3) and connecting rods with pistons (cylinders 4-6).
without picture - Rubber sleeves, assembly aid 9795 for protecting cylinder linings (assembly on connecting rods for cylinders 1-3).
Preliminary work
Notice
Dirt and contamination
^ Risk of damage to units or components
-> Protect components from dirt and contamination.
-> Clean or replace dirty components.
Information
^ All engine repairs must be carried out using only the specified tools.
^ Only these tools have been tested and approved.
Information
^ Photos taken with a digital camera are helpful for dealing with complicated line routing.
1. Remove the engine.
2. Remove the transmission.
3. Remove the flywheel.
4. Mount the engine on the engine assembly support.
5. Remove front silencer.
6. Remove rear silencer.
7. Remove engine carrier.
Engine carrier and holder for front silencer
8. Remove exhaust manifold with catalytic converter.
9. Drain engine oil.
9.1. Unscrew drain plug and collect emerging oil.
9.2. Then screw in drain plug with a new sealing ring and tighten to the specified torque.
-> Tightening torque: 50 Nm (37 ft lb.)
10. Loosen three external Torx screws (E10, M8 x 12) on the hydraulic pump pulley (do not unscrew fully).
11. Remove the drive belt.
11.1. Unscrew screws for hydraulic pump pulley and remove the pulley.
12. Disconnect cable plugs -1 and 3- on the intake-air distributor on cylinder bank 1-3. Unscrew one external Torx screw (E10, M6 x 12) -2- used to secure the cable duct.
Cable plugs on intake-air distributor 1-3
1 - Cable plug on engine compartment temperature sensor
2 - Cable duct mounting on cylinder bank 1-3
3 - Cable plug on control valve for tank ventilation
12.1. 3.8-liter engine only: Pull off cable plug and vacuum line on control valve for tuning flap.
Control valve for tuning flap
1 - Cable plug on control valve for tuning flap on the resonance tube.
2 - Pull off line on control valve.
13. Disconnect positive crankcase ventilation line on the resonance tube -1- and unclip it at the intake-air distributor -arrows-. Turn the line towards the rear.
Positive crankcase ventilation line on cylinder bank 4-6
13.1. Unscrew one external Torx screw (E10, M6 x 12) -2- used to secure the cable duct to the intake-air distributor.
14. Loosen holder at the oil-fill pipe. To do this, unscrew three external Torx screws (E10, M6 x 12) -2-.
Oil-fill pipe holder and positive crankcase ventilation line
14.1. Unclip positive crankcase ventilation line -3- at the oil-fill pipe.
15. Completely remove intake-air distributor.
15.1. Unscrew six external Torx screws (E10, M6 x 35).
15.2. Completely remove the intake-air distributor and resonance tube.
15.3. Clean sealing faces and close off ducts with adhesive tape or stoppers.
15.4. Replace moulded seals.
16. Remove oil filler neck -1-.
16.1. Unscrew two external Torx screws (E10, M6 x20) -2- and pull the connection piece out of the crankcase.
Oil filler neck
16.2. Close off opening with adhesive tape or a stopper.
16.3. Replace O-ring.
17. Remove the generator.
17.1. Pull off cable plug and unscrew M8 hexagon nut on the B+ line. Remove B+ line.
17.2. Loosen external Torx screws (E12, M8) by two to three turns -1- and fit screw insert (E12) with short extension on the screw head. Loosen threaded sleeves in the unit carrier by tapping gently with a plastic hammer.
Loosening fastening screws for generator
17.3. Unscrew the right-hand screw, leave the left-hand screw in place and take out the generator.
18. Remove upper heat shields -1- for ignition coils.
18.1. Unscrew two external Torx screws (E10, M6 x 12) -2- on each and remove the heat shields.
Upper part of heat shield
19. Unplug several cable plugs and disconnect ground straps for ignition coils.
Cable plugs on cylinder head cover
1 - Connectors for ignition coils
2 - Internal Torx screws (T40) securing ground connection for ignition coil
3 - Hall sender
4 - Solenoid hydraulic valve for valve lift adjustment
20. Remove holder for rear silencer -1-.
20.1. Unscrew four external Torx screws (E12, M8 x 20) -2- and remove holder.
Holder for rear silencer
21. Disconnect B+ line -1- and control line for solenoid switch (terminal 50) -2- at the starter.
Screwing off fastening nuts for cable shoe on the starter
22. Remove positive crankcase ventilation line -1- (air conditioning compressor remains in the vehicle when you remove the engine).
22.1. Open rapid-action couplings by pressing the locking ring -3- and unclip line from the holder -arrow-.
22.2. Replace O-rings on the connection point to the bracket for the oil/water heat exchanger.
Positive crankcase ventilation line
23. Remove hydraulic pump -1- together with the pressure line -2- and return line -3-.
Hydraulic pump and lines
24. Remove housing cover for coolant regulator -1- and coolant intake tube -5- (from the coolant reservoir).
24.1. Unscrew one external Torx screw (E10) M6 x40 -2-, three M6 x 50 screws -3- and takeoff the cover and thermostat.
24.2. Unscrew two external Torx screws (E10, M6 x 12) -4- and pull off the intake tube. Replace O-rings.
Intake tube and coolant regulator housing
25. Remove oil separator -1-.
Oil separator
25.1. Unscrew two external Torx screws (E10, M6 x 25) -2- and pull off the oil separator. Replace O-rings.
26. Remove coolant pipe with coolant hose and connection piece (Henn coupling).
26.1. Unscrew three external Torx screws (E12, M8 x 70) -2- on the unit carrier.
Unit carrier
26.2. Unscrew two external Torx screws (E10, M6 x 12) -2- and remove the coolant pipe and connection piece -1-.
Coolant pipe with hose and connection piece
27. Remove the coolant distributor and coolant hoses (on the oil/water heat exchanger).
27.1. Open two spring band clamps -1- and pull the hoses -2- off the oil/water heat exchanger.
Coolant hoses on heat exchanger
27.2. Unscrew two external Torx screws (E10, M6 x 25) -2- and pull up the distributor -1-.
Coolant distributor
Coolant distributor -1- and pipes -2- for the coolant pump and thermostat housing.
Coolant distributor and connecting pipes
27.3. Replace O-rings -1- and grease new O-rings with Kluberplus Gel (Part No. 000.043.205.93).
O-rings for connecting pipes for coolant distributor
28. Unplug several cable plugs at the engine, unclip all cable holders and unscrew two external Torx screws (E12, M8 x 16) on the cable duct.
^ Solenoid hydraulic valve for camshaft control (top of cylinder head)
^ Fuel pressure sensor on fuel collection pipe, cylinder bank 4-6
^ Oil pressure and temperature sensor on bracket for oil/water heat exchanger
^ Fuel injectors
^ Knock sensors
^ Flow control valve on high-pressure pump
^ Coolant temperature sensor on unit carrier
^ Pressure-regulating valve and oil-level sender on oil pan
28.1. Remove engine wire harness.
29. Remove transport eyebolt.
29.1. Unscrew two external Torx screws (E10, M6 x 25)
30. Remove fuel connection line -1- to the fuel collection pipes.
30.1. Loosen two external Torx screws (E10, M6 x 12) at the clamps.
30.2. Unscrew two external Torx screws (E10) on the fuel line holders. One screw on the center holder M6 x 16 -3- and one screw on the right holder M6 x 60 (screw point for bracket for oil/water heat exchanger) -2-.
30.3. Screw off three union nuts (a/f 17) -4- and remove the line. Collect emerging fuel with a cloth.
Fuel connection line to the fuel collection pipes
31. Remove oil/water heat exchanger -1-.
31.1. Unscrew six internal Torx screws (T30, M6 x 20) -2- and remove heat exchanger.
31.2. Collect any drops of fluid with a clean cloth and clean the sealing faces.
31.3. Replace O-rings.
Oil/water heat exchanger
Information
^ The bracket for the oil/water heat exchanger must not be removed at an angle or levered off at one side. This can break the aluminium supports in the crankcase.
32. Remove bracket for oil/water heat exchanger -1-.
32.1. Unscrew six external Torx screws (E10): four M6 x 45 screws -2- and two M6 x 60 screws -3-. Pull the bracket up and out.
32.2. Close off oil ducts with stoppers.
32.3. Replace two O-rings at the top -4- and four O-rings on the underside.
Bracket for Oil/water heat exchanger
33. Remove fuel collection pipes.
33.1. Unscrew four external Torx screws (E10, M6 x 30) -1- and pull the fuel collection pipes -2- out of the cylinder heads.
Threaded joint for fuel collection pipe
33.2. Close off fitted bores in the cylinder head with stoppers.
34. Remove knock sensors (mark installation position using a water-resistant marker).
34.1. Unscrew one external Torx screw (E12, M8 x 16) on each sensor and remove sensors.
35. Remove fuel lines for the high and low-pressure side.
35.1. Loosen and screw off hexagon union nuts on the high-pressure pump -1-. Low-pressure line -2-: a/f 17, high-pressure line -4-: a/f 14.
35.2. Unscrew one external Torx screw (E10) M6 x 16 -3- and one M6 x 12 screw -5- at the retaining points and remove the lines.
Fuel lines for high/low-pressure connection
36. Remove high-pressure pump.
Heat shield for high-pressure pump
36.1. Unscrew three external Torx screws (E10, M6 x 12) on the heat shield and remove the heat shield.
36.2. Unscrew three external Torx screws (E10) on the support: two M6 x 25 screws -1- and one M6 x 40 screw -2-.
36.3. Unscrew two external Torx screws (E10, M6 x 25) -3- and pull out the pump.
36.4. Replace O-ring.
37. Remove vacuum line -1- for brake booster.
37.1. Unscrew external Torx screws (E10, M6 x 12) -2- and pullout line at the vacuum pump.
Vacuum line for brake booster
38. Remove vacuum pump.
39. Remove lower coolant guide -1-.
39.1. Unscrew six external Torx screws (E10, M6 x 25) -2-.
39.2. Check moulded seals and replace if necessary.
Lower coolant guide
40. Use turning device 9773 -1- to turn the engine clockwise at the vibration damper until the TDC 1/4 marking on the vibration damper is aligned with the bore in the crankcase.
TDC marking on cylinder 1/4 on vibration damper
40.1. Secure the engine using one of the locating pins 9595/1 -2- on the vibration damper.
41. Remove vibration damper.
41.1. Loosen and unscrew six external Torx screws (E12, M8 x 25 x 1) and remove the vibration damper.
41.2. Check dowel sleeve and crankshaft flange for damage.
42. Loosen bracket for coolant pump -1-.
42.1. Turn the belt tensioner clockwise as far as it will go at the hexagon (a/f 30). Lock the tensioner at the crankcase bore using an M8 screw (e.g. M8 x 50) -2-.
42.2. Unscrew four external Torx screws: one M8 x 70 (E12) -3-, one M8 x 50 (E12) -4-, one M6 x 20 (E10) -5- and one M8 x 25 (E12) -6-.
Bracket for coolant pump
42.3. Unscrew one M10 threaded bolt (engine carrier mounting) -7- (two M10 lock nuts).
43. Remove coolant connection pipe -1- to the thermostat housing.
43.1. Unscrew one external Torx screw (E10, M6 x 12) -2- on the retaining bracket for the crankcase.
Coolant connection pipe to thermostat housing
43.2. Pullout pipe -1- on the thermostat housing.
44. Remove thermostat housing -2-.
44.1. Unscrew three external Torx screws (E10) M6 x 25 -4- and one M6 x 50 -3-.
Thermostat housing
44.2. Turn bracket for coolant pump slightly to the right.
44.3. Pull the thermostat housing -1- down at the unit carrier (double O-ring seal) and lift it off at the connecting tube -2- to the coolant pump at the same time.
44.4. Pull off bracket for coolant pump -1-. Replace O-rings -2 + 3-. Check seal for damage and replace it if necessary.
O-rings for coolant pipes at coolant pump
44.5. Replace moulded seal on the connecting tube -3-.
Thermostat housing and connecting tube for coolant pump
45. Remove unit carrier (coolant distributor housing). The screws for the engine connection piece -2- and the additional attachment for the coolant pump bracket -3 (left) and 5- have already been removed.
45.1. Unscrew another external Torx screws M8 x 50 -3 (right)- and one M8 x 35 -4-. Remove carrier, check dowel sleeve for damage and replace if necessary.
45.2. Replace moulded seals.
Unit carrier
46. Remove cover for positive crankcase ventilation.
46.1. Cover on cylinder bank 1-3 -1-: Unscrew three external Torx screws (M6 x 20) -4- and replace O-ring -3- and moulded seal -2-.
Cover on positive crankcase ventilation 1-3
46.2. Cover on cylinder bank 4-6 -1-: Unscrew two external Torx screws (M6 x 20) -3- and replace O-ring -2-.
Cover on positive crankcase ventilation 4-6
47. Remove solenoid hydraulic valves for camshaft control.
47.1. Unscrew two external Torx screws (E8, M5 x 12) on each valve and pull off the valves.
47.2. Replace O-rings.
48. Remove hall senders on the cylinder head cover.
48.1. Unscrew one external Torx screw (T40) M6 x 16) on each and pull off the hall senders.
48.2. Replace O-ring.
49. Remove solenoid hydraulic valves for valve lift adjustment.
49.1. Unscrew two external Torx screws (E8, M5 x 12) on each valve and pull off the valves.
Disassembly
Disassembling the engine
Notice
Dirt and contamination
^ Risk of damage to units or components
-> Protect components from dirt and contamination.
-> Clean or replace dirty components.
Information
^ Guide the timing chains with your hand when turning the crankshaft so that they do not get stuck in the crankcase.
1. Remove cylinder head cover.
1.1. Unscrew one external Torx screw (E12, M8 x 20) for the engine ground strap on cylinder bank 4-6 and remove the ground strap.
2. Check visually to see which cylinder bank is at overlapping position. Remove this cylinder bank first.
2.1. Check visually to see which cylinder bank is at overlapping position. Remove this cylinder bank first.
Cam positions:
^ Overlapping position of cylinder bank 1-3: Cams on cylinder 1 are facing outward at a slant.
^ Overlapping position of cylinder bank 4-6: Cams on cylinder 4 are facing inward at a slant to the spark-plug recess.
Cam position on cylinder 1 at overlap
Cam position on cylinder 4 at overlap
2.2. If the camshafts are at overlapping position, square markings can be seen on the outlet and intake camshaft (data matrix code).
Marking on camshafts 4-6 at overlap
3. Remove camshafts.
Information
^ Position hydraulic tappets on a surface you have prepared and labelled yourself in accordance with their installation position in the cylinder head.
^ Components have been run in in fitted bores and must not be confused.
^ Do not use magnets for removal or installation. This can cause the components to malfunction.
4. Remove hydraulic tappets.
4.1. Pull six bucket tappets -1- and six switching tappets -2- out of the fitted bores in the cylinder head with your thumb and index finger. Do not use a magnet.
Hydraulic tappets for valve control
4.2. Lay components on clean, labelled cardboard.
Example of laying aside bucket tappets
5. Remove tensioning and guide rails.
5.1. Cylinders 1-3: Unscrew one bearing pin -2- for the tensioning rail and two bearing pins -1- for the guide rail.
Bearing pins on cylinder bank 1-3
5.2. Pull out the guide and tensioning rails -1- using a pair of flat-nosed pliers.
Guide and tensioning rails
5.3. Lay the timing chain in the chain slot.
5.4. Pull oil supply valve on vacuum pump -1- out of the cylinder head using a pair of flat-nosed pliers -arrow-. Replace O-ring.
Oil supply valve on vacuum pump for brake booster
Oil supply valve on vacuum pump
5.5. Cylinders 4-6: Unscrew two bearing pins -2- for the guide rail and one bearing pin -3- for the tensioning rail.
Bearing pins on cylinder bank 4-6
5.6. The bearing pin for the tensioning rail 4-6 -1- is longer than the five other pins -2- for the timing chain rails.
Difference between bearing pins
5.7. Replace O-rings on the bearing pins.
6. Remove cylinder head and cylinder head gasket.
7. Pull out twelve displacement bodies -1- on cylinder bank 1-3 using a pair of flat-nosed pliers.
Piston marking and displacement bodies on cylinder bank 1-3
8. Turn the engine at the engine assembly support so that the oil pan is at the top.
9. Remove the oil pan.
10. Remove coolant pipe -1- for the coolant pump.
10.1. Unscrew two external Torx screws (E10, M6 x 12) -2- and remove the pipe.
Coolant pipe for coolant pump
11. Remove oil pump and oil guide.
12. Turn the engine at the engine assembly support so that cylinder bank 1-3 is facing upwards.
13. Remove pistons for cylinders 1-3.
14. Remove crankcase half 1-3.
14.1. Unscrew 19 external Torx screws for the outer cross bolt connection. The threaded bolt must be removed for screw -17-.
Outer cross bolt connection
15, 16 and 17 - External Torx screw, M8 x 35
18 - External Torx screw, M6 x 40
19-32 - External Torx screw, M6 x 25
33 - External Torx screw, M8 x 120
14.2. Loosen and unscrew through-bolt screws (E14) M10 x 195 in the opposite sequence to the tightening sequence.
Through-bolt screws on crankcase
1-14 -External Torx screw M10 x 1.5 x 195 with sealing washer
14.3. Check screws for damage and replace them if necessary or only replace the sealing washers.
15. Unscrew two mounting parts 9590 for bolting crankcase half 1-3 to the engine support.
16. Lift off crankcase 1-3.
16.1. To do this, put on heat-resistant gloves and heat the sealant at the joint slightly with a hot-air gun.
16.2. Lift up crankcase half 1-3 at the positions shown using a large slotted screwdriver.
Lever positions on crankcase
16.3. Slide in two pieces of wood above the oil-pump pressure channels and lift up the crankcase half using a mounting lever.
Mounting lever position on crankcase
17. Remove pistons and connecting rods on cylinders 4-6.
17.1. Remove connecting rods 1-3 on the crankshaft.
18. Remove and dispose of crankshaft sealing rings.
19. Lift crankshaft and timing chains out of crankcase half 4-6.
Crankshaft and timing chains in crankcase half 4-6
19.1. Remove bearing shells from the crankcase halves and dispose of them.
19.2. The deviation sample catalogue for the Cayenne can be used to assess the cylinder linings.
20. Clean the crankcase and sealing surfaces.