Timing Belt and Timing Gears Removal, Inspection and Installation

REMOVAL

If abnormal noise is heard from the timing belt, first check its tension adjustment. This procedure can be performed without removing the front covers (see paragraph 5 of the Balance Shafts and Drive Belt Removal, Inspection and Installation section).

PROCEDURE

1. Bring the engine to No. 1 cylinder TDC. To access the timing belt, remove the front covers and the balance shaft drive belt (refer to Positioning No. 1 Piston at Top Dead Center (TDC)).

2. With the tensioner nut loosened, push the tensioner roller down, then tighten the nut. The timing belt can now be removed from the timing gears.

If the old belt is in serviceable condition and will be reinstalled, mark the direction of rotation and the position relative to the gears of the shafts with chalk or white paint.
3. If necessary, remove the camshaft gear: insert a large screwdriver through the hole in the gear casting, then carefully loosen the mounting bolt with a socket wrench.

Take care not to allow the camshaft to rotate while loosening the bolt of its gear!
4. Removing the camshaft gear provides access to the two rear timing belt cover bolts and to the camshaft oil seal.

INSPECTION
PROCEDURE

Check the tensioner roller for free rotation by hand, then move it from side to side to check for bearing play. Inspect the teeth of the timing gears (look for chips, cracks and other mechanical damage). Check the camshaft end play. Carefully inspect the timing belt on both sides for signs of wear (especially the tooth flanks), cracks, cuts, abrasion and oil contamination. Replace any defective components.

While the belt is off, replace the water pump as well (see Cooling and Heating System chapter).
INSTALLATION
PROCEDURE

1. If removed, install the camshaft gear and tighten its mounting bolt to the specified torque.
2. Make sure the engine is still at TDC of the compression stroke for cylinder No. 1 (see Positioning Cylinder No. 1 Piston at Top Dead Center (TDC)).

3. Align the timing marks on the camshaft and crankshaft gears with the corresponding marks on the engine block.

The marks on both sides of the camshaft pulley must be aligned with the upper edge of the cylinder head.

4. Make sure the rear balance shaft is locked using a bolt or a 6 x 100 mm bar wrench. Fit the timing belt over the gears, moving counterclockwise in the following order: crankshaft gear, tensioner, water pump, camshaft gear.

5. Loosen the tensioner nut to allow the belt to tension. Tighten the nut and install the balance shaft drive belt (see Balance Shaft Gears and Drive Belt: Removal, Inspection and Installation).
6. Adjust the tension of both belts (see Balance Shaft Gears and Drive Belt: Removal, Inspection and Installation). Turn the crankshaft two full revolutions by the crankshaft pulley bolt, stopping again at TDC of the compression stroke for cylinder No. 1. Make sure all timing marks have returned to their original positions. Repeat the belt tension adjustment (see step 5 of Balance Shaft Gears and Drive Belt: Removal, Inspection and Installation).
7. Install the remaining components in the reverse order of removal. When installing the crankshaft pulley, lubricate the threads and the underside of the bolt head.

Do not use an impact wrench to tighten the pulley bolt.