Disassembling Engine
NOTE:
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.
- Remove cylinder head cover.
→ 158219 REMOVING AND INSTALLING CYLINDER HEAD COVER .
- 1.1. Unscrew one external Torx screw for the engine ground strap on cylinder bank 4-6 and remove ground strap.
- Check visually to see which cylinder bank is at overlapping position. Remove this cylinder bank first.
- 2.1. Cam positions on intake -1- and outlet camshaft -2-:
- Overlapping position of cylinder bank 1-3: Cams on cylinder 1 are facing outward at an angle.
- Overlapping position of cylinder bank 4-6: Cams on cylinder 4 are facing inward at an angle with respect to the spark-plug recess.
Cylinder 1:
Cylinder 4:
- 2.2. If the camshafts are at overlapping position, rectangular markings -1- can be seen on the outlet and intake camshaft (data matrix code).
- 2.1. Cam positions on intake -1- and outlet camshaft -2-:
- Remove camshafts.
→ 150520 REMOVING AND INSTALLING CAMSHAFTS (INCLUDES SETTING TIMING) .
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.
- Remove hydraulic tappets.
- 4.1. Pull bucket tappets -1- and switching tappets -2- out of the fitting bores in the cylinder head. Do not use magnets.
- 4.2. Lay components on a clean, labelled surface.
- Remove tensioning and guide rails.
- 5.1. Cylinders 1-3: Unscrew one bearing pin for the tensioning rail -2- and two bearing pins for the guide rail -1- .
- 5.2. Pull out the tensioning and guide rails -1- using flat-nosed pliers -3- .
- 5.3. Lay the timing chain in the chain slot.
- 5.4. Pull oil supply valve -1-
on the vacuum pump out of the cylinder head using a pair of flat-nosed pliers. Replace O-ring.
View of oil supply valve -1- with O-ring -2- removed:
- 5.5. Cylinders 4-6: Unscrew two bearing pins -2- for the guide rail and one bearing pin for the tensioning rail -3- .
- 5.6. The bearing pin for the tensioning rail on bank 4-6 -1-
is longer than the five other bearing pins -2-
for the timing chain rails.
- Bearing pins for tensioning rail on cylinder bank 4-6
- Bearing pins for both guide rails and tensioning rail on cylinder bank 1-3
- 5.7. Replace O-rings -3- .
- Remove cylinder head with cylinder-head gasket.
- Pull out displacement bodies -1- on cylinder bank 1-3 using flat-nosed pliers.
- Turn the engine at the engine assembly support so that the oil pan is at the top.
- Remove oil pan.
- Remove coolant pipe -1-
for the coolant pump.
- 10.1. Unscrew two external Torx screws -2- and remove the pipe.
- Remove oil pump and oil guide.
- Turn the engine at the engine assembly support so that cylinder bank 1-3 is facing upwards.
- Remove pistons for cylinders 1-3.
- 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 the screw -item 17-
.
- 15, 16 and 17 - External Torx screw, M8 x 35
- External Torx screw, M6 x 40
- 19-32 - External Torx screw, M6 x 25
- External Torx screw, M8 x 120
- 14.2. Loosen and unscrew through bolts (M10 x 195) in the opposite sequence to the tightening sequence.
- 1-14 - External Torx screw (M10 x 1.5 x 195) with sealing washer
- 14.3. Replace screws.
Once the sealing washers are approved as spare parts in the Spare Parts Catalogue, new sealing washers can be fitted and the screws can be re-used!
- 14.1. Unscrew 19 external Torx screws for the outer cross bolt connection. The threaded bolt must be removed for the screw -item 17-
.
- Unscrew two mounting parts 9590 for bolting crankcase half 1-3 to the engine support.
- 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 -arrows- using a large slotted screwdriver.
- 16.3. Slide in two pieces of wood -1- above the oil-pump pressure channels and lift up the crankcase half using a mounting lever -items 2 and 3- .
- Remove pistons with connecting rods for cylinders 4-6.
→ 131020 REMOVING AND INSTALLING PISTONS .
- 17.1. Remove connecting rods 1-3 on the crankshaft.
- Remove and dispose of crankshaft sealing rings.
- Lift crankshaft with timing chains out of 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.
- Clean the crankcase and sealing faces.