• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

How long does a motor last.

#1
Ok I have a 400 size motor that seems to be dieing I have had it a while now how long do they last? When I fly the plane I have to keep wot just to keep it flying this plane use to fly great when I land it now the motor is hot but the esc and battery are cool to the touch is there something I should look for? is there anyway to fix it? and can it be a bad esc thats not getting hot? Thanks for the info.
kevco8201
 

earthsciteach

Moderator
Moderator
#2
How confident are you of your battery? And, is the motor rubbing on anything causing drag? In my experience, when a motor winding breaks, the motor 'jitters' and won't spin properly.
 

Carbon

Elemental Madness
#3
I had this problem after a crash with my funbat. No smoke yet right? Open up the motor and look for any burn marks. Then check and make sure no magnets are missing. Also check and see if there is any metal debris that could be causing a short. If a magnet is look put a dab of CA on it and put it in place.
 

tramsgar

Senior Member
#5
On a well built brushless only the bearings should wear out (after a lot of hours), and those can be replaced. As Carbon says, pick it apart and inspect. Bad bearings makes noise and are not very smooth when turned.
 
#6
On a well built brushless only the bearings should wear out (after a lot of hours), and those can be replaced. As Carbon says, pick it apart and inspect. Bad bearings makes noise and are not very smooth when turned.
I second this one. I've lost three motors over the years. Two were bearings. One was broken shaft upon contact with tera firma. Mine had the appearance of losing power, but was making a louder and louder squeal of sorts. I recognized the sound immediately as bearings going out.

sconner
 

tramsgar

Senior Member
#7
I second this one. I've lost three motors over the years. Two were bearings. One was broken shaft upon contact with tera firma. Mine had the appearance of losing power, but was making a louder and louder squeal of sorts. I recognized the sound immediately as bearings going out.
Yes, if the squealing/grinding noise pops in over a certain rpm treshold, it's almost certainly bad bearings (or bad assembly =). It often increases in volume the longer the motor runs, up until it goes totally quiet... It could just be a matter of adding bearing lubricant, often available as accessory to R/C cars.
 
#8
pull my brushless apart from time to time to clean up and inspect. Not that they are worth big money, just because i enjoy seeing how things work. sorta amazing how much crud ends up inside bell after a year or so of belly landings.