Removing and Installing Camshaft Housing - GT3
Removing and installing camshaft housing - GT3Includes:
15 03 21 Removing camshaft housing - GT3
15 03 21 Installing camshaft housing - GT3
Removing camshaft housing - GT3
Tools - overview
Removing camshaft housing - GT3
Preliminary work:
- Remove exhaust system
- Remove intake distributor
- Remove oil container
- Remove oil/water bracket
- Remove coolant guide housing
- Remove bracket for generator
- Remove spark plugs
1. Remove oil extraction pump.
To do so, unscrew the fastening screws and remove the oil extraction pump. Unscrew the three screws on the closure cap and remove the cap.
2. Set engine to top dead centre. To do so, only push the generator bracket into place. Set engine to top dead centre. Turn the engine using the belt pulley in running direction until the TDC markings on the belt pulley and on the generator bracket coincide. Remove bracket for the generator.
3. Remove valve cover.
Unscrew the valve cover screws (17 pieces) and remove the valve cover. If the valve cover is stuck, loosen it by gently tapping with a plastic hammer.
4. Relieve camshaft
For any further work, it is sensible to turn the engine in such a way that the camshafts do not press on the valves.
With cylinder bank 1-3, the cams of the first cylinder should point outwards and diagonally upwards
With cylinder bank 4-6, the cams of the fourth cylinder should point outwards and diagonally downwards.
5. Relieve the timing chain.
In order to relieve the timing chain, the chain tensioner and the guide rail between the camshaft sprockets must be removed. Remove both the hexagon-head bolts of the chain tensioner. Remove the chain tensioner cover and the chain tensioner.
6. Remove the guide rail.
Remove the three hexagon-head bolts on the upper guide rail between the camshaft sprockets and remove the guide rail.
7. Remove the chain sprockets of the camshafts.
When removing the chain sprocket of the inlet camshaft, the former must be held with special tool No. 9653 as shown in the diagram, in order to prevent the timing chain from being burdened. Stop the chain sprocket of the exhaust camshaft with special tool No. 9653/1. First remove the chain sprocket of the exhaust camshaft, then the adjuster of the inlet camshaft.
8. Remove oil guide housing.
To do so, unscrew the three hexagon socket head bolts and remove the oil guide housing forwards. The left and right oil guide housings are of different lengths. If the oil guide housing is stuck, loosen the thrust bearing cover.
9. Remove the thrust bearing cover.
In order to remove the thrust bearing cover of the camshafts, unscrew the remaining six hexagon-head bolts and remove the thrust bearing cover forwards.
10. Removing camshafts.
Unscrew the fastening screws of the six camshaft bearings alternately in 1/2-turn steps in the given order, until the camshaft is completely free of tension. If the bearing saddles are stuck, loosen them with a light tap at the side with a screwdriver handle.
11. Remove camshaft bearing saddles.
Lift the camshaft bearing saddles up and off. The bearing saddles must not be exchanged or twisted under any circumstances. Therefore it is sensible to sort the bearing saddles. The bearing saddles possess a matching number to the respective cylinder head and an identification showing the installation position. Lift the camshafts carefully up out of the camshaft housing.
12. Remove the flat-based tappets.
Pull the flat-based tappets upwards out of the cylinder head. In order to avoid confusing the corresponding flat-based tappets, lie them on a prepared sheet of paper as shown in the diagram.
13. Remove the camshaft housing. Unscrew the 18 hexagon-head bolts of the camshaft housing. Unscrew the camshaft housing bolts as shown in 1/2-turn steps from the outside inwards.
14. Remove the camshaft housing.
Remove the camshaft housing upwards, moving it evenly and without tilting. Make sure that the flat-based tappet guides are not damaged.
15. Remove the seals.
Remove the seal between the camshaft housing and the cylinder head. Do not use the seal again.
Installing camshaft housing - GT3
Tools - overview
Tools - overview
Installing camshaft housing - GT3
1. Insert chain box.
Replace lower seal on chain box. Tighten the five hexagon socket head bolts of the chain box with a commercially available socket with socket wrench insert a/f 6 (Commercially available tools, Chapter 2.4, No.: 17-1). The two indicated screws are longer. Tightening torque: 23 Nm (17 ft. lbs.)
2. Replace seals.
Replace the seals on the upper chain box and the seal between the cylinder head and the camshaft housing. Make sure that the designation "TOP" faces upwards.
3. Insert guide rails.
Insert the shorter, curved guide rail in the chain tensioner. Insert the longer guide rail in such a way that the slot points towards the crankcase. The guide rails of the left and right sides of the engine are of different lengths. The guide rail of cylinder bank 4 - 6 is longer.
4. Tighten guide rails.
Equip the three fastening screws of the guide rails with a new sealing ring and screw in place. The two lighter anodized screws must go into the crankcase. Ensure that the guide rails engage in the central position in the chain box. Tightening torque of the three screws: 31 Nm (17 ft. lbs.)
5. Place the camshaft housing in position.
Place the camshaft housing carefully in position. Make sure that the flat-based tappet guides are not damaged.
6. Mount the 18 hexagon-head bolts.
Prepare and position the 18 hexagon-head bolts. Tighten the bolts from the inside outwards in the shown sequence.
Note;
- The fastening screws on the camshaft housing must be of 10.9 quality. If the quality is 8.8, the screws must be replaced.
- Tightening torque: 28 Nm (21 ft. lbs.)
- Initial tightening: 23 Nm (17 ft. lbs.)
7. Insert flat-base tappets.
Before inserting the flat-based tappets, smear them with a thin coat of clean engine oil. Make sure without fail that the flat-based tappets are not confused with each other.
8. Install camshafts.
Apply a thin coat of Optimol Optipit (00004320417) grease on the camshaft bearing surfaces. Insert the camshafts into the camshaft housing.
Designation position
9. Set engine to top dead centre. Using a universal holder, mount a dial gauge on each of the cylinder heads in such a way that it is possible to measure from the gauge on the piston crown from cylinder 1 or 4. Turn the engine in running direction until no further deflection takes place on the dial gauge or until the first and fourth cylinders are at top dead centre.
10. Insert camshafts. With cylinder bank 1-3, insert the camshafts in such a way that the cams of the first cylinder point inwards and diagonally inwards.
View of a camshaft, cyl. 1
11. Make sure that the timing chain lies above the camshafts. Place the camshaft bearing saddles in their original installation position. Pay attention to the matching number to the camshaft bearing housing. The installation numbers on the bearing saddle and on the camshaft bearing housing must point towards each other. Place the thrust bearing cover on top. It must be ensured that the camshafts are properly positioned in the bearing surfaces. Screw in fastening screws (M6x30) by hand. Tighten the thrust bearing cover and the camshaft bearing saddles in the sequence shown. Push both camshafts towards the engine support. Use a plastic hammer for this purpose. Grease the bearing surfaces of the double bearing saddle and fit. Fasten the bearing saddles only when the double bearing saddle lies absolutely flat on the camshaft housing. Tightening must be carried out evenly. Tightening torques: Thrust bearing cover: 13 Nm (9.5 ft. lbs.) Bearing saddles: 13 Nm (9.5 ft. lbs.)
12. Mount the oil guide housing.
The oil guide housings of the individual cylinder banks are of different lengths (right (cylinders 4-6) 27 mm, left (cylinders 1-3) 31 mm). Replace the three hexagon socket head bolts, bond them in with Loctite 270 and tighten them to 9.7 Nm (7.0 ft. lbs.).
13. Mount the inlet camshaft adjuster.
Place the inlet camshaft adjuster on the inlet camshaft and at the same time place the timing chain on the inlet camshaft adjuster. Place the fastening screw in position, but do not tighten it. Make sure that the timing chain is fed correctly in the guide rail.
14. Mount the chain sprocket of the exhaust camshaft.
Clean the assembly surfaces of the exhaust camshaft and of the chain sprocket and remove all oil and grease. Place the chain sprocket for the exhaust camshaft into the timing chain and place them together onto the exhaust camshaft. Mount the driver for the oil pump and place the fastening screw in position, but do not tighten it. The inscription "left" must be legible on cylinder bank 1-3 and the inscription "right" on cylinder bank 4-6.
15. Mount the guide rail between the camshaft wheels.
Tighten the three hexagon-head bolts to 13 Nm (9.5 ft. lbs.).
16. Mount the auxiliary chain tensioner.
In order to remove play from the timing chain, mount the auxiliary chain tensioner No.: 9401. Turn the hexagon on the chain tensioner until the ring on the piston is no longer visible.
17. Set the camshafts (timing).
Check once more with the dial gauge whether the engine is at top dead centre. Then flange special tool No.: 9661 on the rear of the sealing surface of the camshaft housing. Screw in fastening screws only by hand.
18. Place the staking tool in position.
Position the plates in such a way that the text is legible in a normal way. Place the individual plates into the assembly frame.
19. Turn the camshafts with an open-ended wrench until the corresponding plate of the staking tool can be pressed easily into the slot on the camshaft.
20. Tighten the camshafts.
Before the camshafts are tightened, the adjusting unit must be turned with special tool No.: 9653 as far as the right stop. Tighten the camshafts to 30 Nm (22 ft. lbs.). Then remove the plates from the frame of the staking tool. If the camshaft is tightened with the staking tool, there is a danger that the camshafts may be damaged.
21. Stop the exhaust camshaft with the tool 9653/1 and tighten it with a 90° turn. The camshaft must not be turned in the process.
22. Stop the inlet camshaft with the tool 9653 and tighten it with a 130° turn. The camshaft must not be turned in the process.
23. Set the timing.
Rotate the crankshaft of the engine through 720° and check the timing setting.
Set the timing of cylinder bank 4 - 6.
Rotate the crankshaft of the engine 360° further. On cylinder bank 4 - 6, insert the camshafts in such a way that the cams of the fourth cylinder point outwards and diagonally outwards. Install camshafts analogous to cylinder bank 1 - 3.
View: Cams cylinder 4
Mount the staking tool on the other cylinder head. Check that the first or fourth cylinder stands at top dead centre. Set the timing with the same procedure as on the other cylinder head.
Caution:
Engine damage if timing is not set correctly!
- Engine must be at top dead centre.
- The opposite cylinder must be at ignition TDC!
Note;
- The staking tool is designed so that the camshafts are set at overlapping TDC. This means that the opposite cylinder must be at ignition TDC. When setting the timing of cylinder bank 1 - 3, cylinder 4 must be at ignition TDC.
When setting the timing of cylinder bank 4 - 6, cylinder 1 must be at ignition TDC.
24. Check the timing.
Remove the staking tool. Turn the engine through two revolutions in running direction. Set engine to top dead centre again. Mount staking tool and check the camshafts on both cylinder heads.
25. Install chain tensioner.
Remove the auxiliary chain tensioner. Insert the chain tensioner in the chain box. Check for the correct position and designation of the chain tensioner. Position the chain tensioner cover with new seal and tighten the two screws to 9.7 Nm (7.0 ft. lbs.).
26. Replace valve cover.
Apply a further bead of sealant (Drei Bond 1209) to the cleaned valve cover (as shown in the picture). No more than five minutes must elapse between starting the application and replacing the valve cover. Apply a bead of no more than 1.5 mm thickness. Tighten screws to 9.7 Nm (7.0 ft. lbs.) from the inside outwards.