Port Motor Wobbles and Vibrates instead of rotating


I replaced my motors with new ones and tested them out tonight. The vertical and starboard motors work perfectly except for the port motor. When it spins it vibrates violently and wobbles in quarter turns. My only guess is that either the bearing is damaged somehow or the wiring was mixed up when I transferred over the wires from the old motors. Any ideas on what might be causing this?


I tested the motor this morning and it is not a wiring problem. This means that the motor is faulty. I assume that the bearing in the motor was damaged when I was removing the c clips. Is there any way to fix the bearing or should I purchase a new motor? By the way I am using the old motors not the new 2.7 motors.



You should be able to remove the motor bell by removing the c clip again. After that, with a little bit of force you should be able to pop out the bearings to replace them. You will find a bearing in the top of the motor wiring and in the bottom. If you are going to replace the bearing it might be worth upgrading them to stainless steel or nylon of some type while your at it. I wish I could give you a link for the new bearings but I am not sure of the sizing. You might also need to add a dab of glue to keep the new bearing in.

Hope this helps!


Thanks @Patrick2 for the advice. I will probably just buy a new motor instead of replacing the bearing.


I have also had some intermittent problems motor commands and the motors running.

I upgraded to the BlueRobotics thrusters in order to get better long term performance in salt water.

I have had some issues with the thrusters working 100% post upgrade, I am starting to think I may have a wiring, soldering or ESC issue.



Yes, that might be easier.It can never hurt to have a couple of extra of
these motors since they are relatively cheap. It can ruin an expedition if
you suddenly have a motor go out.




If you have a 2.6 or earlier OpenROV, where you have removed the C-clip and can take the motor bells off for cleaning, make sure that, when re-installing the motor bell, that you never let it “snap” into place. The snapping action can pop out the rear bearing, leading to, well, a wobbly motor…

When you’re re-installing the motor bell, hold onto it firmly and gradually slide it into place, feeling that the axle has seated into the rear bearing properly.

BTW, reinstalling the rear bearing is not a big deal. If you take the motor off of it’s base, you’ll probably have the bearing just drop right out. You can then press fit it back into the motor.



I appreciate the information @Walt_Holm. I didn’t realize that “snapping” the motor bell on to the motor could lead to a wobbly motor. I did refit the bearing, however it still wobbled.