2582500 - S12 ENGINE BUZZING'

There is a constant, loud noise coming from the area of the engine, which is repeated at constant intervals
Results of the tests
0CHECK BELT TENSIONAll OKProblems metOperation
1.2 8vCheck the belt is not too tautContinue to Step 2Belt tension excessiveRestore correct tension Op.   1092B64 
1CHECK BELT TENSIONAll OKProblems metOperation
1.9 DIESELCheck the belt tensioners and, in particular, the condition of the bearingsContinue to Step 2Belt tensioner bearing damagedChange the mobile belt tensioner Op.   1092G14 
2CHECK AUXILIARY SHAFT BELTAll OKProblems metOperation
Check whether the whistling disappears when the belt is disconnected.
Do not let the engine run for long with the belt disconnected
Continue to Step 3The whistling remains constantContinue to Step 4
3ALTERNATOR CHECKAll OKProblems metOperation

Check the alternator and, in particular:

  • The condition of the bearing
  • That the pulley is correctly fixed
Continue to Step 4Alternator bearing damagedOverhaul the alternator Op. 5530A18
Pulley fixing not correctRestore the correct pulley fastening
4WATER PUMP CHECKAll OKProblems metOperation
Check the water pump and, in particular the condition of the bearing.Continue to Step 5Water pump bearing damagedReplace the water pump Op.   1088C10 
5CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentFault persistsSearch for the fault starting from another symptom'