2888451 - S21 NOISE' GEARBOX / AT TAKE-OFF

With the engine running, when the various gears are engaged, there is a noise during take-off: the noise varies as the speed varies
Results of the tests
1GEARBOX SHAFT FIXING CHECKAll OKProblems metOperation
Check that the nuts fixing the gearbox main and layshafts are correctly tightened ( Op.   2110B20  Continue to Step 2Nuts not tightenedRestore the correct tightening
2CHECKING THE GEAR SETAll OKProblems metOperation
Check the crown wheel and pinion reduction ( Op.   2110D20  )

In particular

  • it should not be worn or damaged
  • there should not be excessive clearance
  • the ring gear fixings should not be slack
Continue to Step 3Reduction gear damagedRestore the clearance or, if necessary, replace the reduction gear
3CHECKING PLANET CARRIERAll OKProblems metOperation
Check the wear of the satellite carrier bearing or the housing in the differential housing ( Op.   2110D20  )Continue to Step 4Differential case wornReplace the differential casing
4CHECKING CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'