At the heart of every electric RC vehicle is the motor, or the “driving force” —because, let’s face it, as soon as a motor fails, the fun stops. Motor maintenance is extremely important; therefore, if you maintain your motor, the fun is likely to go on and on. While ready-to-run vehicles come with a vast assortment of different motors depending on the manufacturer and the type of vehicle, many come with brushed motors that are sealed and can’t be taken apart. A well-maintained motor is likely to last much longer than one that is covered in dirt and embedded with grit. Keeping your RTR motor running smoothly isn’t really all that hard to do, nor does take a long time to complete.
Step One: REMOVE THE MOTOR
First, remove the motor from the vehicle. More often than not, you’ll need to remove the pinion gear from the motor shaft first in order to remove the motor. Either way, take the gear off and set it to the side. On most RTR vehicles, the motor wires have connectors so you won’t need to unsolder anything—just be careful not to break the plugs when pulling them apart. Take note of the wiring before you disconnect it so you can put it back together exactly how it was. Most motors are held in with a couple of screws and some washers on them. Remove those screws and keep a small tray around to keep your small parts and your pinion in.
Step Two: THE COMPRESSED AIR TRICK
If you have a sealed motor, you are limited to how well you can clean it. Take a clean toothbrush and gently brush the dirt and grime away from the bushings or bearings—take care to not push the dirt in deeper. Another option is compressed air, but only use this after you get the majority of the dirt off the exterior of the motor. Then, use the compressed air and blow dirt out of the motor using the vent holes; you can even try using the motor mounting holes to blow the motor out.
Step Three: GIVE IT A BATH
Water dipping is a trick old-school guys used to break in their motors, but it would also help clean your brushed motors. Never use this method on brushless motors. You will need a cup of water and your motor wired back to your electronics so it works just like if you mounted it in the vehicle. Put enough water into the cup so that you can submerge your motor in it. Next, turn on your radio and your electronics just like you were going to run the vehicle. Run the motor, and hold it in your hand while you turn the throttle trim up until the motor is running at a nice, steady rpm. You don’t want the motor going at full speed but you also don’t want it going too slowly. With your motor submerged in the water, let it run for about 10 minutes. As the motor runs in the water, the brushes will contour to the shape of the commutator and help the motor produce more efficient power back in your vehicle. After the time is up, remove it from the water and the other electronics. Let it dry, put some oil on the bushings or bearings, and let it sit for a few hours.
REBUILDABLE MOTOR MAINTENANCE
When you have a motor that can be disassembled, you can get in there and clean things up. However, this process tends to be very involved. On these type of motors, the endbell comes off by removing the screws holding it in place. Once the screws are removed, start with the end from which the armature sticks out. Take your time and gently remove the endbell. Next, take note of the order of the shims and spacers because you’ll need to put it back together the same way it came apart. You can now pull the armature out and wipe that clean. If you don’t have a comm cutter, simply use a pencil eraser to freshen up the surface of the comm. You are also going to want to remove the bearing from the endbell and use motor spray to blast out the bearings. Add a couple of drops of oil on the bearings, reinstall the shims and spacers as they were before you took it apart, and reinstall the armature. Lastly, reinstall the endbell and snug it up tightly. Give the motor a couple of spins by hand; it should spin fairly easily and feel clean and smooth. If this all checks out, wire it up and give it a little run test in your hand—your motor should now run nice and quietly.
Step Four: BACK WHERE IT BELONGS
Now that your motor is nice and clean, it’s time to mount it back in the vehicle by doing the opposite of taking it out; don’t forget to set your gear mesh. Put a piece of notebook paper in between the gears and tighten the motor. Once you pull out the paper, the teeth of the pinion gear should wiggle a very little bit in the teeth of the spur gear. Be sure the vehicle runs quietly after you reinstall the motor—this is a tell-tale sign of the condition of your gear mesh. If the vehicle is loud, the mesh is too tight and you need to reset the gear mesh. You also don’t want the mesh too loose, or you will strip the gears.
Once your motor is clean and your mesh is all set, you get to go out and get it all dirty again! The type of terrain you drive in will alter how often you should clean your motor. The best part is that now you have a nice fresh clean motor that’s going to be faster and last longer than the guy that doesn’t take the time to maintain his vehicle!