A: Removing/Installing Camshaft

Camshaft Removal

The camshafts of this engine must be removed/installed with the utmost care. To avoid breaking of camshafts, the loosening and tightening specifications for camshaft bearing caps, as well as the basic setting of camshafts in relation to ignition TDC of cylinder no. 1, must be observed with critical attention.

The following repair notes complement the Microfiche Repair Instructions, Engine 104, Mechanical, Group 05, job number 05-220 "Installing/removing camshafts". Please refer to the microfiche together with this service information.

Note:
The camshafts must only be installed/removed in the basic position.

Basic Position

Figure 1:

1. Piston of cylinder no. 1 at ignition TDC. The camshaft setting bores with 4 mm diameter (arrows) touch the upper edge of the cylinder head (both on the outside). Be sure the camshaft timing adjuster is in the retard position. (This is achieved by ensuring the engine is only rotated in the correct direction of rotation, never backwards, throughout the entire procedure) (Figure 1).

Figure 2:

2. Remove camshaft bearing caps 1 and 8. (arrows) Remove thrust washers on camshafts with axial positioning at the front (Figure 2).

Figure 3:

3. For removing the intake camshaft (13a), first remove bearing caps 9,12 and 14 (Figure 3).

Figure 4:

4. Loosen screws of camshaft bearing caps 10, 11 and 13 alternately in steps of 1 turn each, until the valve spring's upward pressure has been eliminated. Remove intake camshaft with camshaft timing adjuster attached (Figure 4).
Remove thrust washers on camshafts with center axial positioning.

Figure 5:

5. For removing the exhaust camshaft (1a), first remove bearing caps 4, 5 and 7 (Figure 5).

Figure 6:

6. Loosen screws of bearing caps 2, 3 and 6 alternately in steps of 1 turn each, until the valve spring's upward pressure has been eliminated. Remove exhaust camshaft (Figure 6).
Remove thrust washers on camshafts with center axial positioning.

Camshaft Installation

Figure 7:

Note:
Check valve tappets for correct seating and easy movement. Coat camshaft bearings and camshafts with oil. The camshaft identification number can be found at bearing points 3 and 10 (behind the bearing cap, arrows, Figure 7).

The letters behind the camshaft identification number are only a production inspection code.

Figure 8:

7. Insert intake camshaft (13a) in the cylinder head in such a way that the cam lobes on the 3rd cylinder point straight down. First install bearing caps 10, 11 and 13 and finger tighten bearing cap screws then tighten alternately in steps of 1 turn each. (Figure 8).

Figure 9:

8. Align camshaft thrust washer grooves with grooves in cylinder head or bearing cap, and in the case of front axial positioning, install thrust washers.
Install the other camshaft bearing caps. Pay attention to proper installation placement of the camshaft bearings (Figure 9).

Figure 10:

In the case of the intake camshaft with center axial positioning (Figure 10), the camshaft bearing cap (Figure 8, item 11) must be removed once again in order to fit the thrust washers (2c, Figure 10) after the camshaft has been aligned.
Tightening torque of screws of the camshaft bearing caps in 21 Nm.

Figure 11:

9. Insent exhaust camshaft into the cylinder head in such a way that the cam lobes on the cylinder no. 2 point straight down. First install bearing caps 2, 3 and 6 and finger tighten the screws of the camshaft bearing caps; then tighten the screws of the cam- shaft bearing caps alternately in steps of one turn each (Figure 11).

Figure 12:

10. Align camshaft thrust washer grooves with grooves in cylinder head or bearing cap, and depending on the version, install thrust washers for the axial alignment of the camshaft. Install the remaining camshaft bearing caps. Pay attention to the installation placement of the camshaft bearings (Figure 12).

Note:
The operations not described here must be taken from the Microfiche Repair Instructions Engine 104, Mechanical, Group 05, (operation no. 05-220).