Removal and installation timing chains (Audi Q7-4L-D)

1. The installation details of the upper timing chains are shown on illustrations 9.1b-c. The installation details of the lower timing chain of the BTR engine are shown on illustrations 9.1e, and CCFA/CCFC engines are shown in the illustration.

Removal timing chains from camshafts only

2. The power unit cannot be removed.



3. Remove the cover of the corresponding upper timing chain (see Section 39).

4. Using the T40058 tool, turn the crankshaft clockwise to the TDC position (see illustration 4.73a and 35.55).

5. Check that the camshafts are at TDC by locking them with the T40060 tool as described in paragraph 9 of Section 9 (see illustrations 9.10a and 9.10c).

6. Place a cloth under the upper section of the oil pan to collect any leaking oil. Unscrew the plug from the upper section of the oil pan and through the resulting service hole, screw the locking pin No. 3242 into the crankshaft locking hole (with a force of 20 Nm), - see illustration.



If necessary, rotate the crankshaft forward/backward slightly to completely align the bore centers.

7. Wrap the 3.3mm drill bit with electrical tape to prevent cutting yourself on it. Press the left upper timing chain tensioner bar in the direction of the arrow (see illustration 9.13a) and lock the tensioner with the prepared drill (1). Remove the T40060 tool, unscrew the bolt (3 in illustration 9.13b) tensioner bar and remove it. Unscrew the bolts (1) of the guide bar and the bolts (2) of the camshaft sprocket. Remove the sprocket and guide bar.



8. Slowly press the right upper timing chain tensioner bar in the direction of the arrow (see illustration), and lock the tensioner with tool T40071.



Remove the T40060 tool and unscrew the bolts (1 in illustration 9.14b) tensioner bars and bolts (2 and 3) of the camshaft sprocket. Remove the sprocket and tensioner.

9. Before installation, make sure that the crankshaft is locked at TDC with locking pin No. 3242 (see illustration 40.6). The lower timing chain must be installed. Make sure that the camshafts of both cylinder heads are also at TDC by inserting the T40060 tool into their holes (see paragraph 5). If it is not possible to install these devices, slightly turn the corresponding shaft using the T40061 adapter (see illustration), secured with four standard sprocket mounting bolts.

Caution: When turning the camshafts, the crankshaft must not be in the position corresponding to the TDC of any piston. Otherwise, valves and pistons may be damaged. After checking, remove the T40060 tools and do not turn the shafts any further.

10. Install the upper left timing chain together with the camshaft sprocket, guide rail and tensioner rail. The centers of the sprocket's oblong holes must be located above the tapered holes in the camshaft. Tighten the bolts (1 and 3 in Illustration 9.17) tension and guide bars and screw in the two sprocket bolts (2). Do not tighten the sprocket bolts completely; the sprocket must be able to rotate on the shaft without axial displacement. Lock the shaft with tool T40060 and release the chain tensioner by pulling out the drill (4).

11. Install the upper right timing chain together with the camshaft sprocket and tensioner. The centers of the sprocket's oblong holes must be located above the tapered holes in the camshaft. Tighten the bolts (1 in the illustration) tensioner and screw in the two bolts (2) of the sprocket.





Do not tighten the sprocket bolts completely - it should be possible to rotate the sprocket on the shaft without axial displacement. Lock the shaft with tool T40060 and release the chain tensioner by pulling out tool T40071.

12. Using a torque wrench and adapter T40062, apply a force of 20 Nm in the direction of the arrow to the driven sprocket of the right cylinder head shaft drive. Maintaining this force, tighten the bolts (1 and 2 in illustration 9.19a). Then remove the T40062 adapter with the T40060 tool and tighten the remaining sprocket mounting bolts. Tighten the left sprocket mounting bolts in the same manner (see illustration 9.19c), creating a preload of 15 Nm.

13. Unscrew locking pin No. 3242 (see illustration 40.6) and check the timing adjustment as described below.

14. Turn the crankshaft clockwise two revolutions, exactly to the next TDC position, and again lock the crankshaft at TDC with locking pin #3242, tightening it to 20 Nm. If the crankshaft has turned past TDC even slightly, turn it approximately two more revolutions to a position approximately 10° before TDC, and then carefully turn it exactly to TDC.

15. Make sure that all camshafts are at TDC: it should be possible to lock them with the T40060 tools (see paragraph 5). If the camshafts cannot be locked, adjust the timing as described below.

16. Loosen the bolts (And in the illustration) fastenings of the sprocket of the corresponding camshaft by approximately one turn, and unscrew the bolt (B) completely.





Install the T40061 adapter onto the bolts, slightly rotate the shaft and insert the T40060 device (see illustration 9.23), as described in paragraph 9 of Section 9. While holding the shaft in this position, tighten the sprocket mounting bolts to 5 Nm. Then remove adapter T40061 with tool T40060 and finally tighten the bolts to 23 Nm. Repeat this procedure on the other cylinder head, if necessary.

17. Unscrew locking pin No. 3242 and check the timing adjustment again (go to paragraph 14).

18. Tighten the service hole plug in the upper section of the oil pan with a new gasket to 35 Nm.

19. Install the timing chain covers (see Section 39).

Removal and installation upper timing chains

Attention:

• Do not rotate the crankshaft or camshafts when the timing belt is not fully installed.
• If you plan to reuse the chain, mark the front side with paint so that you can install the chain in the same way later (movement of the chain used in the opposite direction is not allowed).

20. Remove the lower timing chain cover (see Section 39).

21. Secure the special key T40049 to the rear side of the crankshaft using two bolts with a threaded section no longer than 22 mm and turn the crankshaft in the direction of the arrow to the TDC position (see illustration 9.28a). Fix the shafts at TDC as described in paragraphs 5-6.

22. Wrap the 3.3mm drill bit with electrical tape to prevent cutting yourself on it. Press the left upper timing chain tensioner bar in the direction of the arrow (see illustration 9.13a) and lock the tensioner with the prepared drill (1). Remove the T40060 fixture from both shafts. Unscrew the bolt (3 in illustration 9.13b) tensioner bar and remove it. Unscrew the bolts (1) of the guide bar and the bolts (2) of the camshaft sprocket. Remove the sprocket, guide bar and left chain.



23. Slowly press the right upper timing chain tensioner bar in the direction of the arrow (see illustration 40.8), and lock the tensioner with tool T40071. Unscrew the bolts (1 in illustration 9.14b) tensioner bars and bolts (2 and 3) of the camshaft sprocket. Remove the sprocket, tensioner and chain.

24. Perform the steps described in paragraphs 9-19. When doing this, install the chains together with the sprockets and ensure that the chains used are installed as before (according to the marks).

Removal and installation the lower timing chain

Note: If you intend to reuse the chain, mark the front side of the chain with paint so that you can install the chain in the same way later (movement of the chain used in the opposite direction is not allowed).

25. Remove the upper timing chains (see subsection above) and the auxiliary drive chain (see Section 41).

26. Press the tensioner bar in the direction of the arrow (see illustration or illustration 9.35) and lock the tensioner by inserting tool T40071.



Unscrew the bolts (1) and remove the guide bar. Then unscrew the bolts (2 and 3) and remove the sprockets together with the chain.



27. Installation is carried out in reverse order.