9
Malfunctions
Gear units
Assembly and Operating Instructions – Gear unit series R..7, F..7, K..7, K..9, S..7, SPIROPLAN
®
W
158
9.1
Gear units
Fault
Possible cause
Measure
Unusual, regular run-
ning noise
• Meshing/grinding noise: Bearing
damage
• Check oil consistency, change bearings
• Knocking noise: Irregularity in the
gearing
• Consult SEW
‑
EURODRIVE
• Deformation of the housing upon
tightening
• Check the gear unit mounting for possi-
ble deformation and correct if necessary
• Noise generated by insufficient
stiffness of the gear unit founda-
tion
• Reinforce the gear unit foundation
Unusual, irregular run-
ning noises
• Foreign objects in the oil
• Checking the oil consistency
• Stop the drive, contact
SEW
‑
EURODRIVE
Oil leaking from inspec-
tion cover
• Seal of the inspection cover leak-
ing
• Tighten the screws of the inspection
cover and observe the gear unit. Con-
tact SEW
‑
EURODRIVE if oil is still leak-
ing.
• Seal defective
• Contact SEW
‑
EURODRIVE.
Small amounts of oil
leak from the oil seal
during run-in phase.
• Function-related pseudo-leakage • There is no fault. Remove with soft, lint-
free cloth and keep monitoring it.
Film of moisture around
the dust lip of the oil
seal
• Function-related pseudo-leakage • There is no fault. Remove with soft, lint-
free cloth and keep monitoring it.
Oil leaking from the oil
seal.
• Oil seal leaking/defective
• Check sealing system. It may be neces-
sary to contact SEW
‑
EURODRIVE.
Oil leaking from motor
(e.g. terminal box or
fan)
• Too much oil
• Check oil level, correct if necessary
• Gear unit not ventilated
• Vent gear unit
• Oil seal leaking/defective
• Check sealing system. It may be neces-
sary to contact SEW
‑
EURODRIVE.
Oil leaking from flange
• Flange gasket leaking/defective
• Check sealing system. It may be neces-
sary to contact SEW
‑
EURODRIVE.
• Too much oil
• Check oil level, correct if necessary
• Gear unit not ventilated
• Vent gear unit
Oil leaking from breath-
er valve.
• Too much oil.
• Check oil quantity, correct if necessary
• Function-related oil mist
• There is no fault.
• Drive not installed in proper
mounting position.
• Install breather valve correctly and ad-
just the oil level.
• Frequent cold starts (oil foaming)
and/or high oil level.
• Install oil expansion tank.
Output shaft does not
turn although the motor
is running or the input
shaft is rotated.
• Shaft-hub connection in the gear
unit interrupted.
• Send in the gear unit/gearmotor for re-
pair
21932786/EN – 05/2015