cleaning electric motors
#2
I have used compressed air, , taken them apart and cleaned them in the sink with soapy water, rinsed and dried, re-oiled bearings and assembled, spray contact cleaner, spray bottle of alcohol.
Buzz.
Buzz.
Last edited by blvdbuzzard; 08-11-2013 at 07:00 AM.
#3
My Feedback: (8)
Whatever you do, don't turn the motor. Take it apart and clean it first. Small contaminates between the rotor and stator can cause damage if the motor is rotated.
For brushless motors:
Usually there is either a C-clip or a small set screw or two holding the rotor (outside can) to the shaft. Could be on both ends depending on the motor. Once these are removed the motor can be pulled apart. It takes some force as there are pretty strong magnets inside, so be careful with it. You are left with the stator (inside "core"), usually two bearings (not always), and the prop shaft. A good visual inspection should indicate if you need to pull the shaft and bearings. Unless you really buried it you probably don't have to get that deep. Check the shaft for straightness and the bearings for damage/dents/dirt. Take the opportunity to clean and oil the bearings - once cleaned up, just put a drop or two of oil on the outside of the bearing seal (they are dirt seals, not moisture proof) and spin them. Usually you can go ~500 flights between oil applications if they are good Japanese bearings, but since you're in there, might as well do it now.
With the rotor removed, take the opportunity also to inspect the magnets. The magnets are glued to the inside of the 'can'. They should all be lined up - see if one shifted forward/aft. Spitting a magnet in flight is usually catastrophic to the motor, but catching it early can be easily repaired with the right adhesive. There may be a thin metal retainer that helps keep the magnets from shifting. Inspect that too.
The bearings are the only moving parts in the motor - they are the only things that need to be lubricated. A damp rag is fine to clean everything else. You can use a toothbrush to clean between the magnets and windings. Make sure you dry it, compressed air is a gift.
For brushless motors:
Usually there is either a C-clip or a small set screw or two holding the rotor (outside can) to the shaft. Could be on both ends depending on the motor. Once these are removed the motor can be pulled apart. It takes some force as there are pretty strong magnets inside, so be careful with it. You are left with the stator (inside "core"), usually two bearings (not always), and the prop shaft. A good visual inspection should indicate if you need to pull the shaft and bearings. Unless you really buried it you probably don't have to get that deep. Check the shaft for straightness and the bearings for damage/dents/dirt. Take the opportunity to clean and oil the bearings - once cleaned up, just put a drop or two of oil on the outside of the bearing seal (they are dirt seals, not moisture proof) and spin them. Usually you can go ~500 flights between oil applications if they are good Japanese bearings, but since you're in there, might as well do it now.
With the rotor removed, take the opportunity also to inspect the magnets. The magnets are glued to the inside of the 'can'. They should all be lined up - see if one shifted forward/aft. Spitting a magnet in flight is usually catastrophic to the motor, but catching it early can be easily repaired with the right adhesive. There may be a thin metal retainer that helps keep the magnets from shifting. Inspect that too.
The bearings are the only moving parts in the motor - they are the only things that need to be lubricated. A damp rag is fine to clean everything else. You can use a toothbrush to clean between the magnets and windings. Make sure you dry it, compressed air is a gift.