Inspection - Timing Belt Sprockets, Timing Belt Tensioner Pulley and Idler Pulley, Timing Belt

TIMING BELT SPROCKETS, TENSIONER PULLEY AND IDLER PULLEY

1. Check the camshaft sprocket, crankshaft sprocket, timing belt tensioner pulley and idler pulley for excessive wear, cracks and damage.

Replace if necessary.

2. Check that the timing belt tensioner pulley and idler pulley rotate smoothly and freely, and make sure there is no excessive play or abnormal noise when rotating.

Replace if necessary.

3. Replace the pulley if signs of grease leakage from its bearing are found.

TIMING BELT

1. Check the belt for contamination or oil deposits. Replace if necessary.

Minor belt contamination can be removed with a dry cloth or shop towel. Do not use solvents for this purpose.

2. During engine overhaul or belt tension adjustment, inspect the belt carefully. If any of the defects listed below are found, replace the belt with a new one.

Description	Condition
1. Hardening of the back side of the belt. • The back side of the belt becomes shiny and so hard that a fingernail pressed against it leaves no mark.
2. Cracks on the back side of the belt.
3. Cracks or separation of the tooth facing material.
4. Severe tooth wear (early stage). • The load-side tooth facing is worn (fabric backing is frayed, rubber base is exposed, belt color has faded to colorless, fabric weave structure is unclear).
5. Severe tooth wear (final stage). • The load-side tooth facing is completely worn and the rubber base is exposed (tooth thickness is reduced).
6. Cracks at the tooth base.
7. Missing tooth.
8. Side face of the belt is worn. A normal belt should have sharply defined side surfaces, like surfaces cut with a knife.
9. Cracks on the side face of the belt.