Blower motor problems

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  #1  
Old 06-01-14, 07:48 PM
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Question Blower motor problems

I am trying to find an air handler blower motor for an older lennox unit #CBS18-51-3P. the current motor in place is about 6 years old and is a GE 5KCP39PG G069AS 1/2 HP 1075 RPM v200/230 ( I have been unable to cross reference this motor on line). The blower motor has been making scraping type noises on start up and vibrates with swishing sounds during operation. I have checked the squirrel cage and it spins freely with no scraping noise and no metal filing are seen anywhere. There is some play in the up and down shaft but not much maybe 1/4" or so. I have also noticed on start up the motor rotates about 10 degrees so the mounting bracket does not appear to be holding it tightly in place. As seen from the pictures below there is no way to tighten the bracket as it sits on top of the motor. I guess its pressed on and there is a rubber bushing between the motor and the bracket that I assume is supposed to hold the motor tight. At this point I am not sure if my problem is the bracket with a possible worn bushing or the motor or both.

In addition to locating the correct motor I am also trying to find the bracket that attaches the motor to the squirrel cage housing bracket ( I think its called a spider bracket though not sure. it is a rather odd way to attach the motor and I am having trouble locating the part.) Since its not holding the motor tight anymore this may be my whole problem rather than the motor as I assume the motor is supposed to remain tight). I have attached photos of the mounting bracket. Any help you can give me on this would be greatly appreciated.
 
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Last edited by greggome; 06-01-14 at 08:12 PM.
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  #2  
Old 06-02-14, 03:17 PM
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Try cross referencing the CPN number on the motor.
Does that motor have a run capacitor with a high value? (like 40uF)

Do you see a small trail of "glitter" in the center of the blower housing? The blower wheel may be coming apart at the hub.
 
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Old 06-02-14, 06:01 PM
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Just tried cross referencing the CPN# 21c13925301. No luck. The run capacitor is a 20 mfd uf. I have pulled the housingunit with the motor and squirrel cage partially out allowing me to have a better look. I suspected something was rubbing due to the sound the motor was making but did not see any metal shavings or glitter that would indicate something was scraping or abrading.
 
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Old 06-02-14, 06:30 PM
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You've got a 4 ton horizontal Coil Blower Unit there but I can't much info on it.
It appears older than six years old.

update....
Are you here in the states..... that air handler appears to be a 50hz unit which would not be used here.

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Old 06-02-14, 06:43 PM
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I believe that I read of a 1986 unit with that model number. It is the motor thats 6 years old.


I have never liked that type of resilient mount motor. I always get an OEM motor from the manufacture so that I know it will fit properly.


There is another option but I can't say that I recommend it...

The belly band brackets are much easier to install. I have used this type to install a universal motor when the old motor had the rabbit ears welded to the motor but have never tried it to replace that type of motor.

Amazon.com: blower motor bracket

I see 5 inch and 5.5 inch diameter brackets.
 
  #6  
Old 06-02-14, 07:32 PM
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found the lennox motor # 78f9001 but not sure about the bracket.
 
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