Valve Spring: Service and Repair

Removing And Installing Valve Springs And/Or Valve Stem Seals

Part 1:

Part 2:

Part 3:

Removing, Installing
1 Remove camshafts (77 and 78)
2 Remove spark plugs (22)
3 Remove cover (21) of engine wiring harness at the component partition
4 Bolt on supporting bridge (02) with slide (7)
- Bolt supporting bridge (02) onto camshaft bearings 1+5 and 6+10, use collar bolts (1) for camshaft bearing caps for this step.

5 Rotate piston of cylinder to be processed into TDC
- Rotate crankshaft at central bolt of vibration damper (62), hold timing chain (73) up for this step so that it does not jam when crankshaft rotating.

NOTE: Installation:
- Before installing the camshafts, turn crankshaft back again into initial position.
- This is necessary to enable the colored markings in the timing chain (1) to be used for setting the timing.

6 Remove hydraulic valve clearance compensation elements (3) (bucket tappets)
- at the relevant cylinder

7 Install retaining lock for crankshaft/ring gear
- After setting the cylinder to be processed to TDC in order to prevent the crankshaft or the piston being turned any further.

8 Connect cylinder leak tester
- Screw connection hose (4) of cylinder leak tester into the relevant spark plug hole.

9 Pressurize compression chamber
- to about 5 bar.

10 Attach lever depresser (09) with thrust piece (05) into slide (7) and align
- Position thrust piece (05) vertically at valve spring retainer (15) and align parallel to slide (7).
- Fix thrust piece (05) in place with screw (8) to prevent it turning.

11 Remove top valve spring retainer (15) and valve spring (17)
- Compress valve spring (17)

CAUTION:
- Do not allow valves to touch the piston crown otherwise they will be bent.
- Use tweezers (6), magnet pin or magnetic finger to remove valve collet halves (14).

NOTE: The valve springs (17) of the inlet valves and exhaust valves are identical.

12 Replace valve stem seals

NOTE:
- Inspect surface of valve stems for roughness and formation of burrs (visual inspection or with nail).
- Replace valves with a rough stem surface or formation of burrs.

13 Remove bottom valve spring retainer (20)

Inspecting
14 Inspect top and bottom valve spring retainers (15 and 20)
- Inspect valve spring retainers for pitting, replace if necessary

15 Install in the reverse order.