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You will find in this section the causes and remedies to the main problems related to timing belts: clean break, ragged break, loose teeth, side wear, worn land area, irregular wear on belt back, worn teeth, cracks on the belt back, tooth swelling.

Clean break

en_timingbelt_detail_01
Causes:
  • Incorrect handling during installation
  • Use of inappropriate tools during installation
Actions:
  • During the installation operations, do not twist or bend the belt excessively
  • During assembly, do not use inappropriate tools or levers to fit the belt on the pulleys; if there are flanges on the pulleys, do not force the belt and fully loosen the tensioner to guarantee minimum amplitude of the belt
  • Replace the faulty belt

Ragged break

en_timingbelt_detail_02
Causes:
  • Penetration of foreign matter in the transmission
  • Locking of a transmission component
  • Excessive assembly tension
  • Contact with fuel, petroleum derivatives or solvents
Actions:
  • Check the correct fastening of the transmission components and protective case, and its integrity
  • Check the wear condition of the components and verify their correct operation
  • Tension the belt correctly
  • Replace the faulty belt

Loose teeth

en_timingbelt_detail_03
Causes:
  • Low working tension of the belt
  • Loss of tension in the belt
  • Penetration of foreign matters in the transmission
Actions:
  • Check the belt tension and tension it correctly
  • Check the integrity and correct fastening of the tensioner and other transmission components
  • Replace the faulty belt

Side wear

en_timingbelt_detail_04
Causes:
  • Misalignment of the tensioner or one of the transmission components
Actions:
  • Check the integrity and correct fastening of the tensioner and other transmission components and reset the alignment if necessary
  • Replace the tensioner and/or pulley if worn
  • Replace the faulty belt

Worn land area

en_timingbelt_detail_05
Causes:
  • Excessive tension
  • Worn pulleys
Actions:
  • Replace the worn rigid component
  • Replace the belt and reset the correct working tension
  • Replace the faulty belt

Irregular wear on belt back

en_timingbelt_detail_06
Causes:
  • Locking of a transmission component
  • Worn pulleys
Actions:
  • Replace the worn rigid component
  • Replace the belt and reset the correct working tension
  • Replace the faulty belt

Worn teeth

en_timingbelt_detail_07
Causes:
  • Irregular tension
  • Pulleys with worn teeth
  • Belt tooth profile not compatible with the pulley notches
Actions:
  • Reset the correct belt tension
  • Replace the worn rigid component
  • Check compatibility between the belt tooth profile and the pulley notches
  • Replace the faulty belt

Cracks on the belt back

en_timingbelt_detail_08
Causes:
  • Operation at excessively high or low temperatures
Actions:
  • Check the working environment temperature and use belts produced with heat-resistant compounds
  • Replace the faulty belt

Tooth swelling

en_timingbelt_detail_09
Causes:
  • Contamination by solvents, lubricants or coolant
Actions:
  • Handle with clean hands as much as possible
  • Remove any contaminant leakage from the engine
  • Replace the faulty belt