Alfa Romeo alfa 33 Workshop Manual page 213

Trouble
Noisy both during acceleration
and deceleration (drive shaft
assy already checked)
Transmission is noisy when in
curve, both with speed engaged
or when in neutral (drive shaft
assy already checked)
Transmission is noisy when in
neutral (vehicle is not moving)
Transmission is noisy when in
reverse gear
Engagement/disengagement of
speed is not easy
Speeds become disengaged
May 1983
Probable cause
Differential gears are worn or
l
damaged
Excess play of hypoid
l
Crown gear securing screws are
l
loose
Bevel pinion shim is worn or
l
damaged
Pinion shaft retaining nut is loose
l
Excess play in gear train
l
Teeth of planetary and side gears
l
are worn, damaged or show evi-
dence of pitting
Irregular variations of driving
l
torque
Not enough oil
l
Reverse gears are worn or damaged
l
First of all it should be established if the trouble is caused by the gearbox or by
the control system. If the clutch still transmits torque when the pedal is pushed-
down, it means that it is not disengaged. Verify if the clutch properly couples
(pedal is released) and uncouples (pedal is pushed-down) the engine to the gear-
box casing. If clutch is not faulty, the trouble originates either from the gearbox
or from the control system.
Bushing on outer speed selector
l
lever is worn
Gearbox outer linkage needs adjust-
l
ing and/or lubrication of joints is
insufficient
Stroke of outer linkage parts is not
l
sufficient due to excess play
Not enough oil in gearbox-differ-
l
ential casing
Synchronizing units are faulty
l
Inner controls are deformed or
l
worn
Sleeves and gears are worn or
l
defective
Excess end-play of the gear that
l
becomes disengaged (Noisy both
during acceleration and deceler-
ation)
13-32
Corrective action
Replace gears
Check and replace, if necessary
gears
Tighten
Replace shim
Check gearbox components and
then tighten the nut
Adjust gear train
Replace differential casing
Adjust engine idling
Fill up to correct level
Replace defective parts
Replace bushing
Check linkage, joints and controls
Check the system and, if necessary,
repair or replace worn parts
Fill-up to correct level
Refer to "Synchronizing unit is faulty"
Repair or replace defective parts
Replace worn parts
Verify adjustment of gear train