DIY Home Improvement Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
45 Posts
Discussion Starter #1
At the end of last winter I had to replace the blower motor in my electric furnace. The motor hadn't burned out. The rotor wasn't rubbing on the stator, or at least didn't seem to be. The motor still seemed to be working fine other than one issue. When the fan was running, I would hear very loud metallic banging noises. It was getting worse. I watched the fan run and spotted the problem. I pulled the whole blower assembly out of my furnace and found that the motor shaft had an excessive amount of end play, over a half inch, and that the fan was hitting the bolts on the front of the motor. I checked carefully to make sure that the fan was not loose and moving on the shaft. It wasn't. I also found that if I loosened the fan and slid the fan slightly away from the motor, the fan would hit the blower housing instead. I replaced the motor.

The new motor had no end play in its shaft when I installed it. It's only been in use for a little over four months, but now has about 1/4" of end play. Not enough end play for the fan to be hitting anything yet, but I assume that's coming. Is this a common problem with these motors or is something else causing this to happen?
 

·
Administrator
Joined
·
40,845 Posts
Not uncommon for a shaft to have some play in it after some use.
 
  • Like
Reactions: Koldhammer

·
Registered
Joined
·
13,595 Posts
The new motor had no end play in its shaft when I installed it. It's only been in use for a little over four months, but now has about 1/4" of end play. Not enough end play for the fan to be hitting anything yet, but I assume that's coming. Is this a common problem with these motors or is something else causing this to happen?
Yes, it's becoming more of a problem as time progresses with the china association. Not only motors but a whole array of products too numerous to mention.

Your new motor had end play ( all do to the best of my knowledge ) even though it's only a few thousandths of an inch but it's anyone's guess what the measurement was ( thank china once more ). Being chinese, for all we know the end thrust bearing may be of some type of pressed cardboard.

When this motor fails take it to a local repair shop, if available, and have new bearings installed. If it's so odd ball that can't be done they quickly will tell you.
 
1 - 4 of 4 Posts
Top