Sumitomo Cyclo HBB, Operation & Maintenance Manual

Cyclo® HBB

Operation & Maintenance Manual

 45

Cyclo® HBB

Troubleshooting

This troubleshooting guide provides assistance in identifying and overcoming common problems in reducers and motors  If you have a  
problem with the reducer and/or the motor that is not listed below, please consult the factory for assistance 

Problem with the Reducer

Possible Causes

Suggested Remedy

Runs Hot

Overloading

Load exceeds capacity of the reducer

Check the rated capacity of the reducer, replace with unit of sufficient capacity 

or reduce the load 

Improper lubrication

Insufficient lubricant

Check lubricant level and increase to recommended levels.

Excessive lubricant

Check lubricant level and reduce to recommended level.

Incorrect lubricant

Flush old lubricant from the unit and refill with correct recommended lubricant 

Vibration or

Noise

Loose foundation bolts

Weak mounting structure

Inspect mounting of reducer  Tighten loose bolts and/or reinforce mounting & 

structure 

Loose hold-down bolts

Tighten bolts 

Worn disc and/or helical 

gearing

Overloading of the unit may result in 

damage to the Helical gearing and/or the 

Cycloid discs 

If helical gearset is damaged, contact the factory  

If Cycloid discs are damaged, disassemble the Cyclo® portion and replace discs  

Re-check the rated capacity of the unit.

Bearing Failure

May be due to lack of lubricant

If output bearings are damaged, contact the factory  

If bearings in Cyclo® portion are damaged, replace the affected bearings  Clean & 

flush the reducer and fill with the correct type and quantity of lubricant 

Overload

Check the rated capacity of the reducer. Replace with unit of sufficient capacity 

or reduce the driven load 

Insufficient Lubricant

Level of lubricant in the reducer not

properly maintained 

Check lubricant level and adjust to factory-recommended level.

Damaged Cyclo® pins 

and rollers

Overloading of reducer

Disassemble Cyclo® portion of reducer and replace ring

gear housing pins and rollers. Check load on reducer.

Output

Shaft/Hub does

not turn

Motor shaft broken

Overloading of reducer can cause

this type of damage 

Replace broken shaft. Check rated capacity of reducer.

Input shaft key missing 

or broken

Replace key.

Eccentric bearing 

broken

Lack of Lubricant

Replace the Eccentric Bearing in the Cyclo® portion  Flush

and refill the unit with the recommended lubricant 

Motor does not turn

Motor

Refer to the “Motor” portion of this Troubleshooting guide 

Oil Leakage

Worn seals

Caused by dirt or grit entering the seal 

area 

Replace the oil seals  The breather filter may be clogged Replace or clean filter 

Leakage into motor

Reducer has been overfilled with 

lubricant 

Check the lubricant level and adjust to the recommended level.

Air breather clogged 

Clean or replace element, being sure to prevent any dirt from falling into the 

reducer 

Improper mounting position, such as 

other than designed mounting angle 

Mount the unit in it’s designed mounting angle