Replacing the timing chain on a 612 series engine
Illustrative material for replacing the timing chain of the 612 series engine is presented in the illustration, which includes all references in the text.
Removing
1. Remove the cylinder head cover.
2. Remove the vacuum pump.
3. Remove the cooling fan assembly.
4. Using a special tool, dismember the chain links and remove it from the engine.
Installation
1. Start a new chain (2) to its regular place and using a special device, articulate the links.
2. Having made the necessary preparations (see Section Removal and installation of timing drive components), install the chain tensioner (14).
3. Check the correct basic position of the camshafts (see Section Checking the basic position of the balancing shaft (628 series motors only)).
4. Install the vacuum pump.
5. Install the cooling fan clutch.
6. Install the cylinder head cover.
7. Start the engine and check it for signs of leak development.
M628
Examination
Replacing the timing chain on a 628 series engine
1 - Inlet camshaft; 2 - Drive belt pulley; 3 - Label; 4 - Blocker
1. Illustrative material for checking the condition of the timing chain of the 628 series engine is presented in the illustration, which includes all references in the text.
2. Evaluation of the degree of chain stretch is made by checking the position of the pulley (2) drive belt on the blocked intake camshaft.
3. Remove a cover of the right head of cylinders.
4. Remove the accessory drive belt.
5. Cranking the engine in the normal direction (arrow), block the intake shaft (1) with the aid of a device (4).
6. If the pulley misalignment (2) is more than 11° (after TDC), the chain should be replaced.
7. When finished checking/replacing, reinstall the accessory drive belt and cylinder head covers.
Removal and installation
Replacing the timing chain on a 628 series engine
1 - Old gas distribution chain; 2 - New gas distribution chain; 010 - Holder
Illustrative material for replacing the timing chain of the 628 series engine is presented in the illustration, which includes all references in the text.
Removing
1. Open the hood and lock it in an upright position.
2. Remove the cylinder head covers.
3. Remove the cover of the first bearing of the exhaust camshaft of the right cylinder head (see Section Removal and installation of timing components).
4. Fix the holders on the right head (010 and 011).
5. Dismember the links and remove the old chain (1) from the engine.
Installation
1. Start a new chain (2) to its regular place and make the articulation of its links.
2. Check the correct basic position of the camshafts (see Section Setting the basic position of the camshafts).
3. Check the correct basic position of the balancing shaft (see Section Checking the basic position of the balancing shaft (628 series motors only)).
4. Remove the holders (010 and 011).
5. Establish a cover of the first bearing of a final camshaft of the right head of cylinders.
6. Install the cylinder head covers.
7. Close the hood.