Action
1. Drain the coolant (undo the drain plug or remove the lower radiator hose). Removing the expansion tank cap will accelerate the draining process.Note
Since there will still be quite a lot of coolant remaining in the engine, always position a suitable receptacle under the vehicle when working on the coolant system.
2. Remove the Poly-V belt and timing cover. See Page 215-1 of Service Manual 2:1 Basic Engine, B258.
** Before removing the timing belt, use a felt pen to mark the face of guide rollers A & B as shown in the sample. This mark should line up with the point on the eccentric adjuster furthest away from the Torx head mounting bolt. Note the approximate position of both marks on this engine.**
** 3. Rotate the engine until # 1 cylinder is at TDC. The crank and camshaft markings should all be in alignment. Install the red and green camshaft locks and the crankshaft lock.
4. Remove upper guide roller B, the timing belt and the belt tensioner bracket.**
5. Turn the crankshaft back to approximately 60° BTDC to prevent damage to the valves and pistons should the # 3 or # 4 cam spin when the locking tool is removed.
6. With green locking tool (included in P/N 83 94 926 cam locking kit) still in place between camshaft sprockets 3 and 4, undo the bolts and remove the tool and camshaft sprockets. See Figure 3, item 4.
7. Remove the rear timing cover retaining bolts one at a time and apply threadlocking compound, Loctite 242 to the bolts. Reinstall and tighten the bolts. See Figure 3, item 11.
8. Fit the new thicker camshaft sprockets with new bolts. Check the position against the markings on the rear timing cover. Secure camshaft sprockets 3 and 4 with the green locking tool (included in P/N 83 94 926 cam locking kit) and tighten the bolts. See Figure 3, item 5 above.
Tightening torque: 37 ft.lbs. (50 Nm) + 60°.
** 9. Fit the belt tensioner bracket. See Figure 3, item 7 above. Remove upper guide roller B to make it easier to install the timing belt.**
Tightening torque: 30 ft.lbs. (40 Nm).
10. Remove the water pump. See Figure 3, item 8 above.
11. Clean the sealing surfaces and fit a new 0-ring. Smear acid-free Vaseline on the sealing surfaces and 0-ring and fit a new water pump. See Figure 3, item 9 above.
Tightening torque: 18.5 ft.lbs. (25 Nm).
12. Turn the crankshaft forward to just before 0° and fit crankshaft locking tool KM800-10 (included in P/N 83 94 926 cam locking kit) on the crankshaft. Carefully turn the crankshaft in the same direction of rotation as the engine until the arm rests against the flange of the water pump and then tighten it.
** 13. Temporarily remove the locking tool from the crank to make it easier to install the timing belt.**
** 14. Install the timing belt. Start by aligning the marks on the belt with the corresponding marks on cams $3 & 4. Next, thread the belt around the lower guide roller A and the crankshaft sprocket.
15. Lock the belt onto the crank sprocket using the yellow plastic wedge. With the crankshaft alignment tool removed, it is easy to verify that the mark on the belt lines up with the hash mark on the face of the crank sprocket.
16. Route the timing belt around the spring-loaded belt tensioner and match the paint marks on the belt with the timing marks on the sprockets for cams # 1 & 2.
17. Install upper guide roller B. If there was a washer behind it when you removed the roller from the bracket in step # 9, refit the washer.
18. Reinstall the crankshaft lock and tighten it against the hub for the water pump.
19. Adjust the belt tensioner so that the alignment marks are positioned as shown. **
** 20. Remove the yellow wedge from the crankshaft.**
** 21. Make a preliminary setting to upper guide roller B by turning it counterclockwise until your felt pen indicator mark is at the 10 o'clock position as shown below. Tighten the mounting bolt enough to keep the adjuster in place. You don't need to torque it yet.
22. Remove the locks from both banks of cams.
23. Install K-M alignment tool KM800-2 on cams # 3 & 4.
24. Grab the timing belt slightly below the spring-loaded tensioner and tug on it just enough to retard # 3 & 4 cams as shown. You should only move the marks on the cam sprockets counterclockwise by 1 mm, approximately the width of the alignment marks on the cams.**
** 25. Turn lower guide roller A counterclockwise until the marks on # 3 & 4 cams line up with those on K-M alignment tool KM800-2. Tighten the adjuster bolt while holding the eccentric nut with wrench P/N 83 94 983. The eccentric will walk if you don't hold It while tightening the bolt.**
The indexing mark on the guide roller A should end up pointing towards the water pump at approximately the angle shown.
** 26. Move alignment tool K-M800-2 to cams # 1 & 2.
27. Install the green lock between cams # 3 & 4.**
** 28. At this point, the marks on cams # 1 & 2 should be slightly to the left (retarded) of the marks on alignment tool K-M800-2. If not, tug on the belt below the spring-loaded tensioner again to move the marks to the left by 1 mm as shown.**
** 29. Turn the upper adjuster counterclockwise slightly until the marks on the cam sprockets and the alignment tool K-M800-2 line up. Tighten the adjuster.**
** The indexing mark on guide roller B should end up in the approximate position shown.**
** 30. Remove all the locks and locking tool K-M800-10. Turn the engine over twice, installing the crankshaft lock just before reaching TDC on the second revolution. Bring the engine up to TDC and lock the crank in place.
31. Recheck the timing of both pairs of cams. It is possible to make final adjustments without removing the belt and starting all over again by turning the guide rollers slightly.
32. Make your final adjustment to the spring-loaded tensioner as shown.**
** 33. Torque all bolts. Make sure the guide rollers and tensioner don't move during this step
NOTE:
The torque on these components Is critical!
Lower guide roller A: 30 ft.lbs.(40 Nm)
Upper guide roller B: 30 ft.lbs.(40 Nm)
Belt tensioner: 15 ft.lbs. (20 Nm) **
Camshaft pulley bolts: 37 ft.lbs. (5O Nm) + 60°