Timing Belt: Adjustments

Timing Belt, Checking/Adjustment

Special tool: 998 8500

To be carried out 10000 km (6250 miles) (USA: 5000 miles) following belt replacement.

Procedure to be carried out with engine warm to touch (approx. 40°C / 104°F).

CAUTION: See table in specifications if checking/adjustment is carried out at other engine temperature.


Checking





Turn engine to TDC in No.1 cylinder
Remove upper transmission cover (1).

Check that markings on camshaft pulleys are opposite markings on transmission mounting plate.

Check that marking on crankshaft is opposite TDC marking.





Check belt tension
Position gauge 998 8500 between exhaust camshaft pulley and tensioner.

Read gauge.

If belt tension is correct, reading should be between 3.2 and 4.2 units.

If tension is correct, install transmission cover (1). If tension is incorrect, belt must be adjusted as described in operations below.



Adjustment





Slacken tensioner locknut
Remove protective rubber cap in transmission cover.

Slacken locknut.





Turn crankshaft clockwise through one revolution
Camshaft pulley markings should again coincide with markings on transmission mounting plate.

NOTE: Engine must not be rotated counter-clockwise during belt tensioning procedure.





Turn engine further clockwise
Turn engine until camshaft pulley markings are 1 1/2 teeth past markings on transmission mounting plate.

NOTE: Rotate crankshaft smoothly.





Tighten tensioner locknut





Turn crankshaft clockwise to complete one revolution
Turn crankshaft to return to TDC.

Check that all markings coincide.





Recheck belt tension
Position gauge 998 8500 between exhaust camshaft pulley and idler pulley.

Read gauge.

Belt tension should now agree with specified value of 3.9 ± 0.3 units.

NOTE: If reading is still outside correct range. adjust as described below.





Tighten tensioner locknut
Tighten to 50 Nm (37 ft.lb)

Install:
- protective rubber cap over tensioner locknut
- upper transmission cover (1)





Check operation
Test run engine.


Tension timing belt





Slacken tensioner locknut.

Position gauge in measuring zone.

Insert screwdriver between tensioner pulley and end of spring carrier pin.

If belt tension is too low:
Move pulley to adjust reading to 4.4 ± 0.3 units.

If belt tension is too high:
Adjust to obtain reading of 3.4 ± 0.3 units.

Tighten tensioner locknut.

Recheck belt tension.

Complete adjustment.