Most common reasons why a pneumatic motor fails

14 mai 2018

Motor maintenance

The advantage of a pneumatic motor is that it has a simple, robust design. Unlike electric motors, the most common failures can usually be put right rapidly, without any need for expert knowledge, simply by knowing a few tips that we’ll pass on to you here.

First, you need to know that a pneumatic motor does not reach full power until after it’s been in use for about 1 hour (the time it takes to break in the motor).

Before using a new motor or one that has been in storage, we recommend that you add 3 to 5 drops of pneumatic oil to the motor’s feed aperture, then connect it to a well lubricated air network and let it run for 5 to 10 minutes before reaching a ‘normal’ performance level.

The motor doesn’t work at all when you connect it for the first time?

  • Check the feed source

The most common error comes from the feed source or connection. If there’s a pathway problem on the distributor, if you’re using a non-reversible motor (which only rotates in one direction), then the motor won’t rotate at all. On the other hand, with a reversible motor, if the distributor is not connected correctly and the exhaust opening is not the right one, the motor will still work but with reduced power.

  • The applied load is too heavy

The motor does not have the right dimensions for the task in hand. The load exerted is too heavy.

If there is a power problem with a new pneumatic motor, check the air feed (both flow and pressure) as well as the lead and any connections.

The motor started but stopped soon after or suffered a loss of power.

In this situation, it could be that non-filtered air has damaged the motor. Particles may have penetrated the rotor’s interior. The motor has seized, or dust or a tiny chip may have scratched the stator causing the motor to wear prematurely.

Check also that the motor is well lubricated. Insufficient lubrication can cause loss of power.

So you can be sure that the air fed into the motor is clean, dry and correctly lubricated, we strongly recommend using an FRL unit (filtration, regulation, lubrication). This equipment is an essential part of your pneumatic system, guaranteeing the performance and durability of its components. Choose the FRL unit carefully, taking into account the pressure and flow specifications of all the elements incorporated in the pneumatic system.

The motor functioned correctly for several hours and then stopped suddenly, or suffered a loss of power?

  • Some parts of the motor may have worn out prematurely or have been corroded which can happen if the air used is not perfectly dry and lubricated.
  • Too much pressure may have damaged the gears or caused the paddles to wear out more quickly than usual.
  • A maintenance error – the motor has not been correctly reassembled following a maintenance procedure, or was not lubricated when reassembled. Take care also, when reassembling the motor, to check that all the needles of the sockets are in the satellites,  otherwise you risk breaking a tooth which would damage the motor permanently.

Summary of failures / causes and corrections

Summary of failures causes and corrections-1


Pierre-Yves Cote
Pierre-Yves Cote

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