Uniform tooth damage would be normally attributed to a raised
burr on an idler sprocket. Intermittent tooth damage would suggest either the camshaft or crankshaft sprockets
to be damaged. Extent of material loss to belt is normally directly proportional to the pulley damage. Belt failure
could result particularly if the teeth's material loss contaminates the rest of the pulley drive.
ACTION:
Inspect and rectify/renew pulleys as necessary. DO NOT clean
pulleys with metal scrapes or wire brushes, use wooden scrapes or a soft brush. DO NOT clean with solvents as
oil seal damage could result.
BELT BACKING PUNCTURE
FEATURES:
Raised bruise or raised open flat.
CAUSES:
Intrusion of foreign body.
GENERAL:
Normally attributed to ingress of a stone into the belt train.
The stone punctures the belt tooth or valley as it is compressed and passed around a rotating pulley. The intruder
might be exhausted through the back of the belt, or might remain entrapped especially if embedded into a tooth.
Cord fracture can occur creating an immediate weak point and a belt break failure might result.
ACTION:
Ensure belt guards are fitted and that they are effective in
protecting the belt train.
