Atwood Furnace motor bearing problem

[BILLC]

We have a 2002 Monaco Diplomat.  It has an Atwood furnace.  Modle: 8940-III-DCLP tag is on motor.  Serial number: 1409656

A few days ago, I began hearing the bearings "squeal" when the furnace fan was turning...they squealed just a bit every once in a while.  This morning, bearings began squealing much louder and more often.  I turned off the furnace and switched to the two heat pumps.

Looks like it needs a new motor. This is a guess on my part.  

Questions:

1. Best place to buy a motor?

2. Where to find instructions on motor replacement?

3. Can just bearings be replaced?

Thanks for any advice you can give.

Bill Cook

[richard5933]

We went through this about a year ago on our coach. Here's what I found:

1. Not worth replacing just the bearings - the motors don't cost that much so if you're going to go through the effort of replacing the bearings you might was well just install a new motor.
2. You might be able to get a little more time from the furnace if you are able to get oil to the bearings, but once they start squealing it's really just a matter of time till the motor seizes up. Once I had ours apart enough to access the bearings to oil them, I figured I might as well just replace the motor since I didn't want to have to repeat the process in a few months. My time was worth more than the cost of the motor, and we all know that the thing is most likely to seize up on the coldest morning of the year when you really need it.
3. Some of these furnaces were subject to a recall for some serious safety issues. Before spending time/money/effort on a repair check yours to see if it was subject to a recall, and if so was the necessary repair completed properly.
4. Based on my experience with them, Atwood will not sell motors to individuals, only to repair shops/dealers. Not really a problem as motors are easy to get elsewhere.
5. Installation is pretty straightforward if you're good at taking things apart and putting them back together. The manual shows an exploded diagram of the furnace, so I used that as my guide. I also took lots and lots of close-up photos BEFORE taking parts off so that I would know how to put them back.
6. While you're in there, it's probably a good plan to do a routine maintenance on the whole furnace - lots of information about this online.

I didn't verify that this is the exact replacement for your furnace motor, but it's a start:

https://pdxrvwholesale.com/products/atwood-hydroflame-furnace-blower-motor-37357

Here's a link to the thread about my repairs if you want:

Obviously a different and older furnace, but it might help you some.

All that said, these furnaces are not that terribly expensive. Depending on the overall condition of the unit, it might be worth your time to just find another on sale somewhere and swap it out.

Good luck!

 

[wolfe10]

Suspect the fan motor has bushings, not true bearings. As such, a short term fix is to use a light viscosity oil (like sewing machine oil) where the shaft goes into the motor.

Yes, it will take a long skinny screwdriver, etc to get the oil in there.

Again, consider this a short term fix only.

[BILLC]

Rich,

You are a wealth of information.  Thanks so much!  And thanks or the link to the threads.  Good read.

I will check to see if there are any recalls on my unit.

I will check on the price to have a new unit installed, but will probably just replace the motor.  Everything else on the furnace is working fine.

When replacing the motor, we will service the the unit.  Get it cleaned up.  Make it pretty.

Again, Rich, thanks so much for the help.

Bill Cook

[manholt]

Had to do the same, sewing machine oil, on my AC fan last year...still works!  I'm saving my pennies for a new AC/Heat Strip unit...not cheap!  

[BILLC]

Thanks Wolfe10.  I agree, oiling will only be a sort term fix.  Since I have the time, think we will go for the long-term fix instead.

Bill Cook

[rayin]

Armed with the data-plate information and the frame # you may locate a replacement motor easily. If you have an electric motor repair shop nearby they likely have or can obtain a new motor quickly.

[jleamont]

Bill, our Atwood in the last coach had the same issue. Started to squeal at the beginning of a cross country trip thanksgiving day (of course). I did exactly as Brett recommended and it got me a few months of quiet fan operation. Replacing the motor was simple and make sure to order the fan wheel, I did and it was a good thing as the original was stuck on the motor shaft and the plastic was brittle. If I remember it was less that $20 for the fan portion. 

[dickandlois]

On 3/9/2019 at 7:21 PM, jleamont said:

Bill, our Atwood in the last coach had the same issue. Started to squeal at the beginning of a cross country trip thanksgiving day (of course). I did exactly as Brett recommended and it got me a few months of quiet fan operation. Replacing the motor was simple and make sure to order the fan wheel, I did and it was a good thing as the original was stuck on the motor shaft and the plastic was brittle. If I remember it was less that $20 for the fan portion. 

Joe,

      Some of the motors are easier to R and R then others.  I have removed the Blower housing to replace the sail switches - While doing that job one can also clean the motor shaft bushing and apply some silicon grease to the shaft and bushing(bearing) area.  Note, These motor blower bushing are open to dirt and dust.

      The best product to clean them that I have found is CRC spray. It removes all the old lubrication along with the dirt.  Spray some Silicon on the shaft and bushing while the motor is running. Nice thing is they run on 12 volts, but keep you fingers clear on the blower (squirrel  cage) They can wack a finger and that can brake the blower also!

Motor part number is related directly to the system BTU's 

Field  vice - 2 pieces of 2X4 held together with bungee cord(s)

Rich.

[manholt]

Easiest way to find Rich at  a Rally?  Look for a older coach with a body under it !! 😍