Disassembling/Assembling Engine
Disassembling and assembling V6 (BFD) engineTools
Preliminary work
1. Remove engine.
2. Support engine on engine support.
3. Drain engine oil, hydraulic oil and coolant. Turn engine in engine support, if necessary. Dispose of fluid in accordance with legal requirements.
Tools and materials
Special tools
Note: The special tools that are required are for repairing engines'.
Disassembling V6 (BFD) engine
WARNING Danger of cutting oneself on sharp metal edges!
^ Wear suitable protective clothing (e.g. gloves).
Note:
^ Various different types of fluid will emerge while you are working on the engine. Have sufficient cloths and collecting containers to hand. Dispose of fluid in accordance with country-specific regulations.
^ More detailed work instructions can be found in the individual repair descriptions in the Technical Manual. Only the necessary information for disassembly and assembly is provided in the chapters linked by cross-references.
^ References to tightening torques are given separately.
1. Remove drive belt.
2. Remove belt tensioner. To do this, remove three M8 x 30 fastening screws.
3. Remove deflection roller. Lever off the lid and remove deflection roller by loosening the fastening screw.
4. Remove generator. Disconnect cable plug. Then unscrew two M8 x 90 fastening screws and carefully press generator out of the support using a mounting lever. Get an assistant to hold the generator while you remove water hoses.
5. Remove hydraulic pump. To do this, unscrew three fastening screws (two at the front through the pulley and one from behind).
6. Screw off unit holder (three M8 x 40 and two M8 x 28 fit bolts).
7. Remove water pump. To do this, remove three internal-serration screws through the pulley from the front and remove the water pump. Collect emerging coolant. Replace sealing ring.
8. Remove coolant run-on pump at top chain case lid -2-. To do this, pull off cable plug and remove together with coolant hoses. Press pump out of the bracket at the rubber mounts.
9. Screw the sheet-metal holder for the vacuum valves -7- sideways off the intake-air distributor (two M6 studs with a hexagon in the middle -8-). Press support for switch-over pipe control valves out of the bracket. Disconnect cable plugs and lines.
10. Remove oil/water heat exchanger -4- by loosening the coolant hoses and unscrewing the banjo bolt -5-. Unscrew drain plug -9- and drain oil filter. Remove oil-filter housing/engine support arm by loosening five fastening screws -10-. Replace seal.
11. Remove engine wire harness.
12. Loosen and remove the intake-air distributor. Remove vacuum lines and hoses. Remove the sheet-metal holder between the exhaust manifold and intake-air distributor (three hexagon socket head bolts). Unscrew two hexagon socket head bolts at the front and rear sideways at the exhaust side -7 and 12-. Unscrew nine M7 x 40 hexagon socket head bolts at the inlet side using a long socket. Raise the intake-air distributor starting at the exhaust side and tip it off. Remove at the inlet side.
13. Unscrew the secondary air valve (combination valve) -1 to 5-. To do this, unscrew three M6 x 23 fastening screws. Replace seal.
14. Unscrew heat protection shield on exhaust manifold (two M6 hexagon socket head bolts).
15. Unscrew the two exhaust manifolds. To do this, unscrew seven M8 copper nuts (x 2) from the studs on the cylinder head.
16. Remove aluminum water tube -1- under the exhaust manifolds. To do this, unscrew two fastening screws -17- from the holders and pull the spring band clamp and water hose off the flange.
17. Remove fuel distributor pipe. To do this, unscrew four M6 x 26 hexagon socket head bolts -arrows-. Carefully pull the distributor pipe along with the fuel injectors out of the cylinder head.
18. Remove engine support fasteners at the front and rear (M8 hexagon socket).
19. Unscrew the thermostat housing -3- by loosening two M6 x 120 and one M6 x 26 fastening screws. Remove water hoses. Pull off water tube -6- (replace seals).
20. Remove double-mass flywheel (DMF) or drive plate. Remove ten M10 internal-serration fastening screws. The DMF cannot be mixed up.
21. Remove ignition coils and spark plugs.
22. Unscrew all nine fastening screws and two fastening nuts on the cylinder head cover -see illustration-. Lift off cylinder head cover and set it down on a clean surface.
23. Turn engine to the ignition TDC of cylinder 1. To do this, turn the crankshaft so that the notch on the crankshaft pulley is aligned with the marking on the housing cover. It must be possible to insert the camshaft guide T10068 into the rear slits on the camshafts. If this is not the case, turn the crankshaft a further 360° and insert the camshaft guide again.
24. Remove chain tensioner. To do this, remove the chain tensioner to the side on the top chain case lid -arrow-.
25. Remove sheet-metal holder for additional coolant pump -1-.
26. Unscrew both chain case lids (top and bottom). Hall senders can remain fitted on the top chain case lid. Top chain case lid Bottom chain case lid
27. Secure the crankshaft at the pulley using the special arm bracket T10069.
28. Loosen fastening screw on intermediate shaft gear wheel -14-.
29. Loosen camshaft adjuster -4 and 22-. To do this, counter camshafts at the hexagon and loosen the fastening screws on the camshaft adjusters -23-.
30. Remove top tensioning rail -8- and guide rail -24-. Remove two fastening screws for the guide rail -21-.
31. Remove timing chain for camshafts -3-. Remove camshaft adjusters -4 and 22-.
Note: Press the bottom chain tensioner together during removal because otherwise it will push out due to spring tensioning. Secure chain tensioner with a tie-wrap in tensioned state.
32. Remove fastening screw on intermediate shaft -14- and take off gear wheel -13-.
33. Loosen bottom chain tensioner -15-. Hold the chain tensioner in tensioned state and secure with a tie-wrap. Loosen two fastening screws -2 below- and remove tensioned chain tensioner.
34. Remove bottom timing chain -17-. Remove guide rail -18-.
Note:
^ The screws for the camshaft adjuster timing chain housing -1- are micro-encapsulated and can snap during removal. Screws must be replaced.
^ The oil strainer -2- must be checked and cleaned if necessary.
35. Unscrew camshaft adjuster timing chain housing -1-. Do this carefully because the screws -2 above- are micro-encapsulated and can snap easily. Pull off camshaft adjuster timing chain housing. Loosen it if necessary by tapping carefully with a plastic hammer.
Note:
^ Camshaft bearing caps are marked as follows:
^ Even numbers on bearing cap = outlet; uneven numbers on bearing cap = inlet; numbering sequence starting from timing chain side (output), legible from inlet side, housing edges pointed outward, no. 7 and 8 are thrust or guide bearings!
36. Unscrew camshaft bearing covers. Proceed step-by-step from the outside in. Mark the exact position of the bearing covers and place on a clean surface according to installation position.
Note: Grooves and numbers are located in the middle of the camshafts: No. 102 inlet, two grooves -B-, No. 101outlet, one groove -A-!
37. Remove camshafts carefully and place on a clean surface.
38. Unscrew cylinder head. Remove twenty internal-serration screws (thirteen M10 x 110 and seven M10 x 140) in reverse order to the sequence shown (middle screws are longer). Remove cylinder head with the help of an assistant and place it on a clean surface.
39. Take hydro-tappets and roller-type cam followers -14 to 16- out of the cylinder head and lay them on a clean surface in such a way that they cannot get mixed up.
40. Remove cylinder-head gasket.
41. Disassemble oil pump drive.
42. Pull oil retaining valve with an M8 screw -arrow-.
43. Turn engine in engine support.
Note: Connecting-rod bearing caps must be marked and numbered during removal. Retaining lugs of bearing shells are pressed together. The cast lugs of connecting-rod bearings and connecting-rod big end are identical!
44. Remove oil pump.
Note: The flat side of the piston crown always points to the middle of the cylinder block.
45. Unscrew connecting-rod bearing cap -6- and pull out pistons -2- in sequence. Turn the crankshaft back and forth to make room for removing the connecting-rod bearing cap. Join connecting-rod bearing cap and connecting-rod big end together again, mark each one and lay to one side. Connecting-rod bearing caps are legible on alternate sides for each cylinder bank.
46. Remove the crankshaft belt pulley with a helper. To do this, block the pulley using an arm bracket T10069 and loosen the M18 x 40 fastening screw. Replace the fastening screw.
47. Remove the sealing flange behind the crankshaft belt pulley. To do this, remove the fastening screws -A and B- and lever the flange off with a screwdriver.
48. Unscrew crankshaft bearing caps -1- (legible from exhaust side and from opposite the output), mark each one and lay to one side according to cylinders (no. 5 is the thrust and guide bearing). Store the thrust washers -4- and bearing shells -3- along with the corresponding bearing caps.
ATTENTION Damage to sensitive engine components (e.g. speed sensor wheel)
^ Conscientious and precise work
^ Use suitable storage places.
WARNING Risk of crushing your hands when lifting the crankshaft!
^ Hold the very outside of the crankshaft.
^ Wear gloves.
^ Get an assistant to help lift the crankshaft.
49. Prepare a space for the crankshaft that does not impede the speed sensor wheel. Lever out the crankshaft and set it down on a clean surface.
Assembling V6 (BFD) engine
WARNING Danger of cutting oneself on sharp metal edges!
^ Wear suitable protective clothing (e.g. gloves).
ATTENTION Damage to sensitive engine components (e.g. speed sensor wheel)
^ Conscientious and precise work
^ Use suitable storage places.
WARNING Risk of crushing your hands when lifting the crankshaft!
^ Hold the very outside of the crankshaft.
^ Wear gloves.
^ Get an assistant to help lift the crankshaft.
ATTENTION Leaks due to components being at too low a temperature or at different temperatures!
^ If components that are cold or at different temperatures are sealed together by the application of sealant, adhesion problems and leaks can arise due to the build-up of condensation water or component distortion.
^ Components must have reached at least 17°C throughout.
^ Components must not be too hot (distortion).
^ Spare parts that are stored in the cold or heat (strong sunlight), must be brought to room temperature or the same temperature as other parts before installation.
1. Replace crankshaft bearing shells (color markings must match). Insert and oil crankshaft bearing shells (on crankcase side). Make sure the twist lock is positioned in the corresponding cut-out Bearing shell.
2. Insert crankshaft into the oiled bearing.
Note:
^ Bearing covers for the crankshaft are numbered 1 to 7 and the numbers can be read on the side facing the exhaust.
^ Bearing no. 5 is a guide or thrust bearing with two thrust washers at the side.
^ The twist locks or retaining lugs are on the same side.
^ Bearing screws must be replaced.
^ Bearing shells must be replaced. Use only identical color markings
3. Fit thrust bearing no. 5 with thrust washers -4- (insert with grease, lubricating groove facing outwards), then fit the remaining bearing covers -1- (from exhaust side no. 1, numbering legible opposite output).
4. Position bearing covers by tapping with a rubber hammer.
5. Replace bearing screws -2- and tighten to the specified tightening torque in stages from the middle outwards. '10 Tightening torques for Cayenne (engine type BFD)'
6. Turn crankshaft to try it out.
Note:
^ Piston installation instructions must be followed at all times.
^ The cast lugs, twist locks (retaining lugs) -1- and the flat side of the piston crown -2- are on the same side.
7. Insert oiled pistons and connecting rods using a funnel T10147. Turn the crankshaft back and forth as required so that there is sufficient room for installation. Align flat side of piston crown to the middle of the cylinder block. Always align the pins -arrow- on the funnel T10147 to the middle of the cylinder block.
Note:
^ Always replace the connecting-rod bearing shells and oil them before inserting them into the bearing covers.
^ The connecting-rod big end and connecting-rod bearing caps must be aligned according to the cast lugs -B and C-. The retaining lugs of the connecting-rod bearing shells are on one side. Connecting-rod bearing caps are legible on alternate sides.
^ Install connecting rod and connecting-rod bearing caps unrestrained. If necessary, remove them again, position the bearing caps by tapping lightly with a plastic hammer and then refit them.
8. Align the connecting rods of the pistons to the crank pins. Oil the bearings. Position connecting-rod bearing covers in the correct sequence and screw bolts into the connecting-rod big end by hand. Retaining lugs of bearing shells must be pressed together.
9. Position the connecting-rod bearings by tapping with a plastic hammer. Tighten all connecting-rod screws to the prescribed tightening torque. '10 Tightening torques for Cayenne (engine type BFD)'
10. Turn the crankshaft provisionally with belt pulley and fastening screw to check for smooth operation.
11. Turn the crankshaft so that the sender gap on the speed sender ring gear is pointing downwards to the middle (rough TDC presetting).
12. Fit the sealing flange behind the crankshaft belt pulley.
13. Fit the crankshaft belt pulley with a helper. To do this, block the pulley using an arm bracket T10069 and fit the M18 x 40 fastening screw. Use a new fastening screw.
14. Install oil pump.
15. Turn engine in engine support.
16. Install oil pump drive.
17. Insert oil retaining valve with sealing ring in crankcase -arrow-.
18. Turn engine to the ignition TDC of cylinder 1. To do this, turn the crankshaft so that the notch on the pulley is aligned with the marking on the housing cover.
19. Position cylinder-head gasket correctly on the dowel sleeves (inscription pointing upwards) and install the cylinder head.
20. Assemble support element, roller-type cam followers and safety clips or check that they are assembled correctly. Make sure the support elements and roller-type cam followers are joined correctly by the safety clips -1 and 2-.
21. Oil the components. Install support element/roller-type cam follower. Make sure that the safety clip does not slip out of place during installation. The pressure face of the roller-type cam follower -3- must rest on the valve pressure face. This can slip out of place when the camshaft is installed later.
22. Install camshafts.
23. Check that the crankshaft is positioned at the TDC of cylinder 1.
24. Fit timing chain housing. To do this, slide the timing chain housing on to the oiled sealing rings of the camshafts. If necessary, press the sealing rings together in the ring stacks -arrows-. Push the timing chain housing up as far as the centering pins.
25. Fit the four M6 x 30 fastening screws with securing liquid -arrows-. Tightening torque: 8 (6 ft-lb.) Nm.
26. Install camshaft adjusters.
27. Set the timing.
28. Install bottom chain case lid.
29. Install top chain case lid.
30. Fit water tube -6- in water pump housing (tap pointing downwards).
31. Turn engine through two turns at the crankshaft and check the timing again.
32. Install cylinder head cover.
33. Fit oil/water heat exchanger -3 to 5-. Fit oil filter housing/engine support arm -10-. Replace seals -2 and 3-. Tightening torque: 23 (17 ft-lb.) Nm
34. Install fuel distribution pipe and fuel injectors.
35. Insert water pump with new seal and secure from the front through the belt pulley with three internal-serration screws.
36. Place aluminum water tube in installation position. Secure water hoses. Tightening torque: 8 (6 ft-lb.) Nm
37. Fit exhaust manifolds.
38. Fit intake-air distributor.
39. Fit oil dip stick with a new sealing ring and insert into guide tube.
40. Fit unit holder. To do this, insert two fit bolts and three fastening screws and tighten holder. Tightening torque: 23 (17 ft-lb.) Nm
41. Install generator.
42. Install servo pump.
43. Fit engine wire harness.
44. Fit the deflection roller in front of the generator. Press on plastic lid.
45. Fit belt tensioner with bracket using three fastening screws.
46. Fit and tension the drive belt.
Subsequent work
1. Install engine.