Camshaft Timing Chains
Camshaft Timing Chains
Special tools, testers and auxiliary items required
• Counter-holder (T10172) with pin (T10172/2)
• Adapter (T40058)
• Locking pin (T40069)
• Camshaft locator (T40070) (qty. 2)
• Locking Pin (T40071) (qty. 2)
• Multi-point socket (T10035)
Removing
• According to the following description, the timing chains for camshafts remain on engine. If the timing chains for camshafts are to be completely removed, the lower timing chain cover must also be removed => [ Lower Timing Chain Cover ] Lower Timing Chain Cover.
- Remove cylinder head cover: Left => [ Left Cylinder Head Cover ] Left Cylinder Head Cover, right => [ Right Cylinder Head Cover ] Right Cylinder Head Cover.
- Remove left and right timing chain covers => [ Left and Right Timing Chain Covers ] Left and Right Timing Chain Covers.
- Loosen quick-release fasteners - 1 - and - 2 - and remove front noise insulation. Rear section of noise insulation remains installed.
- Insert guide pin of adapter (T40058) so that large diameter - arrow 1 - points to engine. Small diameter - arrow 2 - points to adapter.
- Using socket (T40058), rotate crankshaft in direction of engine rotation - arrow - to TDC.
• The threaded holes - arrows - in camshafts must face upward.
- Mount camshaft locating tool (T40070) on both cylinder heads and tighten bolts - arrows - to 20 Nm.
• The camshaft locating tool (T40070) is correctly positioned when the holes for the cylinder head bolts remain free.
- Unfasten left and right stabilizer bar mountings - 1 - and - 2 -.
- Remove sealing plug - arrow - from cylinder block.
CAUTION!
Do not turn the crankshaft while touching the TDC opening with a finger or personal injury could result.
- Install crankshaft holder (T40069) in the hole - 1 - to 10 Nm. If necessary rotate crankshaft back and forth slightly to completely center holder.
- Mark running direction of left camshaft timing chain with paint.
- Remove bolts - 1 - and - 2 - for camshaft adjuster using multipoint socket (T10035).
- Remove both camshaft adjusters.
- Remove bolts - 1 - and - 2 - and remove chain tensioner.
- Mark running direction of right camshaft timing chain with paint.
- Remove bolts - 1 - and - 2 - for camshaft adjuster using multipoint socket (T10035).
- Remove both camshaft adjusters.
- Remove bolts - 1 - and - 2 - and remove chain tensioner.
Installing
• Always replace bolts that are tightened to torque as well as O-rings and gaskets.
• When turning camshaft, crankshaft must not be at TDC for any cylinder. Valves and/or pistons may be damaged.
• Drive chain for timing mechanism installed => [ Timing Mechanism Drive Chain ] Timing Mechanism Drive Chain.
• Secure crankshaft in TDC position using crankshaft holder (T40069).
• Camshaft locating tool (T40070) mounted on both cylinder heads and tightened to 20 Nm.
- Fully relieve tension of guide rail for left and right camshaft timing chain tensioner - arrow -.
• The piston of tensioning element - 1 - must be driven out completely, thereby releasing retainer - for this chain tensioner must be removed.
• If the tensioning element is to be removed from the chain tensioner, observe the installed position: Hole in housing floor faces toward chain tensioner, piston faces toward tensioning rail.
- Press guide rail of the left and right camshaft timing chain inward - arrow - up to stop and secure chain tensioner with Locking Pin (T40071).
- Clean oil strainer - 3 - in both chain tensioners if necessary.
- Place a new gasket - 2 - onto rear of chain tensioner - 1 -.
- Set chain tensioner in place on left cylinder head and install camshaft timing chain, as shown in the illustration.
- Tighten bolts - 1 - and - 2 -.
- Replace camshaft bolts.
- Place camshaft timing chain onto drive sprocket and onto camshaft adjusters and loosely thread in bolts - 1 - and - 2 -.
• Both camshaft adjusters must be able to still be rotated on camshaft and must not tip.
- Remove Locking Pin (T40071).
- Set chain tensioner in place on the right cylinder head and install camshaft timing chain, as shown in the illustration.
- Tighten bolts - 1 - and - 2 -.
- Replace camshaft bolts.
- Place camshaft timing chain onto drive sprocket and onto camshaft adjusters and loosely thread in bolts - 1 - and - 2 -.
• Both camshaft adjusters must be able to still be rotated on camshaft and must not tip.
- Remove Locking Pin (T40071).
- Set counter-holder (T10172) with pin (T10172/2) in place on camshaft adjuster of left intake camshaft.
- Hold camshaft timing chain pretensioned by pressing on counter-holder in direction of - arrow -.
- Simultaneously, pre-torque camshaft bolt using multipoint socket (T10035) and torque wrench.
• Tightening Specifications 40 Nm.
- Continue holding pretension on intake camshaft and pre-torque bolt - 1 - on the exhaust camshaft.
• Tightening Specifications 40 Nm.
- Tighten camshaft bolts - 1 - and - 2 - on left cylinder head to final torque specification.
• Tightening Specifications: 80 Nm plus an additional 90° ( 1/4 turn).
- Set counter-holder (T10172) with pin (T10172/2) in place on camshaft adjuster of the right exhaust camshaft.
- Hold camshaft timing chain pretensioned by pressing on counter-holder in direction of - arrow -.
- Simultaneously, pre-torque camshaft bolt using multipoint socket (T10035) and torque wrench.
• Tightening Specifications: 40 Nm.
- Continue holding pretension on exhaust camshaft and pre-torque bolt - 1 - on intake camshaft.
• Tightening Specifications: 40 Nm.
- Tighten camshaft bolts - 1 - and - 2 - on right cylinder head to final torque specification.
• Tightening Specifications: 80 Nm plus an additional 90° ( 1/4 turn).
- Remove camshaft locators (T40070) on both cylinder heads.
- Remove crankshaft holder (T40069).
- Using key (T40058) turn crankshaft two complete rotations in direction of engine rotation - arrow - until crankshaft stands at TDC again.
• If rotated unintentionally beyond TDC, turn back crankshaft again approximately 30° and set to TDC again.
• The threaded holes - arrows - in camshafts must face upward.
- Mount camshaft locating tools (T40070) to both cylinder heads and tighten bolts - arrows - to 20 Nm.
• The camshaft locating tool (T40070) is correctly positioned when holes for cylinder head bolts remain free.
- Install crankshaft holder (T40069) directly into hole.
• The crankshaft holder (T40069) must engage in locating hole of crankshaft - 1 -, otherwise repeat adjustment.
- Remove camshaft locating tools on both cylinder heads.
- Remove crankshaft holder.
- Install sealing plug - arrow - of TDC marking with new seal into cylinder block.
Further installation is in reverse order of removal, noting the following:
- Install stabilizer bar.
- Install left and right timing chain covers. Refer to => [ Left and Right Timing Chain Covers ] Left and Right Timing Chain Covers.
- Install cylinder head cover. Refer to: Left => [ Left Cylinder Head Cover ] Left Cylinder Head Cover, right => [ Right Cylinder Head Cover ] Right Cylinder Head Cover.
Tightening Specifications
