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Topic: Furnace fan motor for mid 80's LD.. (Read 6 times) previous topic - next topic
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Furnace fan motor for mid 80's LD..
Yahoo Message Number: 143714
Ok.. I think I pestered you all last year about our furnace needing a new fan as it squeaks badly when first turned on.. It's in our 85 LD and I think is the Atwood if I recall.. I haven't taken it apart yet but was thinking if it's a common part I could order it ahead of time so it's an easy swap job..  So., does anyone know if the fan in these mid 80's furnaces are standard and I can just go online and order easily without worry of getting the wrong item?
 We're leaving for Yosemite for the t-day holiday and I'm trying to get a bunch of odds and ends taken care of..

Tia!!

-- Rick
Re: Furnace fan motor for mid 80's LD..
Reply #1 –
Yahoo Message Number: 143716
Rick I just took a hydo fkame apart last week and managed to oil the sleves and it realk that quiet errned things down. Manuals for most of these are available online.
Start here http://bryantrv.com/owners.html Or send me your model and I may have a pdf I can email you..
Garry
Re: Furnace fan motor for mid 80's LD..
Reply #4 –
Yahoo Message Number: 143727
I took apart the fan motor for our '83 furnace and cleaned and lubed the bearings to free them up. It is best to completely clean off the old lube varnished on the shaft before applying new.

Steve
2004 FL
2013 Honda Fit
Re: Furnace fan motor for mid 80's LD..
Reply #6 –
Yahoo Message Number: 143746
I forgot to ask... Anyone have any good suggestions or pointers for removing the minimal amount of stuff to get that fan out.? I do not have a shop manual for this furnace, and any pointers or tips would be helpful.  Thanks in advance.
Re: Furnace fan motor for mid 80's LD..
Reply #7 –
Yahoo Message Number: 143749
Rick I am sure there is a manual at thr sitefor this unit. If not I am pretty sure I have a pdf that covers it. The pdfs are large but I could give yo access to it on dropbox.

If interested email me at gmfoster at gmail dot com...
The model number would help but the big manual covers many models...
Garry
Re: Furnace fan motor for mid 80's LD..
Reply #8 –
Yahoo Message Number: 143757
Ok.. Found my manual for the furnace in my pile of docs.. It's A bit thin on content but should work okay for this purpose..  In the off chance someone else's wondering what model I had in my 1985 lazy daze Multiplan, the model was in NT-20SE by Suburban.. Which I think was probably their largest non-ducted model at the time..
 I have the two screws out on the bottom of the unit and I was able to disconnect the gas line but it got stuck trying to pull the unit out had to play with it a little bit.  The only thing holding it from coming out, are the 4-5 wires that run to the thermostat and power. Lazy daze did not put much slack on the lines going to the wires and so I may have to rewire it because I cannot get my fingers in there to undo the wire nuts.. I may have to cut the wires...
Re: Furnace fan motor for mid 80's LD..
Reply #9 –
Yahoo Message Number: 143758
By the way... What do I do with the combustion air box gasket that was broken into pieces when I removed the outershell to gain access to the fan motor.? It's in about three or four pieces -- half of it still on the main assembly,  half of it on the outer shell I took off..
 Can I just remove the old gasket and use something similar to what I would use on a car engine -- e.g. Permatex blue gasket sealant material that's in a tube?
Re: Furnace fan motor for mid 80's LD..
Reply #10 –
Yahoo Message Number: 143760
New ones are still available.. The service manual has all the part numbers. You more than likely only have the owners manual..
Garry
Re: Furnace fan motor for mid 80's LD..
Reply #11 –
Yahoo Message Number: 143761
Actually I have the installation and owners manual. It includes the part numbers and product breakdown by part. The question is where to get the parts, I realize I can get them online but I'm kind of in a time pinch. I've got the motor partially disassembled -- I took the backplate off and I'm going to pull the front plate off where the motor contacts are..

I will say that I find the motor spins rather difficultly IMHO.. no free spinning here...  I did plug it into the bench supply and it did not squeak but I know it's the source of my problems..

I will call local RV supply places nearby tomorrow to see if they have any parts - particularly the gasket I need to put it back together..
Re: Furnace fan motor for mid 80's LD..
Reply #12 –
Yahoo Message Number: 143762
Needed a furnace gasket in my old 1986 LD a few years ago. Nowhere to be found. Went to Allied Trailer Supply in San Leandro. Funky little shop on E 14th Street. But, they have everything, all the old stuff. Brought in the old gasket, they had lurking in some bottom drawer somewhere, a small sheet of the old asbestos (gasp!) material, from which they were able to cut another gasket. Worked like a charm. Allied Trailer Supply has been in business since 1962, and I don't think they've ever throw anything away. If you're in the Bay Area, it should definitely go on your list of supply houses. Ttheym ay even have some of that gasket material left. See if they'll cut you one.

Kathy Lautz 1999 MB
1999 MB
Re: Furnace fan motor for mid 80's LD..
Reply #13 –
Yahoo Message Number: 143763
ok.. uploaded a bunch of photos associated with this job.. They can be found at the link below..

Anyway, now that I've got the motor completely disassembled and a bunch of 'crap' came out in the process, I'm wondering what exactly I need to do to clean it.. I used some acetone to clean the varnish and other dried up crap off the armature on the side where the brushes contact -- it's nice and clean.  However, I feel like I need to possibly soak the end case that has the brushes mounted as it has a floating bearing of some sort -- I'm not convinced the bearing actually spins though -- but maybe??  It won't currently for me -- but I can pivot the bearing a bit with the help of a screwdriver or the armature.

So.. What's the procedure to clean the ends of the motor housing where the armature spins? I don't think the back-end of the housing has any bearing as it doesn't want to spin -- is it just a grease point and nothing more?

Thanks again Garry and Steve for the insight provided thus far!

Here's the link to the picasaweb album with the associated pics from todays adventure..

P.S. I did get the furnace out without cutting wires -- a bit of fiddling around got it so I was able to undo the wire-nuts -- of course not before blowing a fuse as the hot 12V wire grounded out against the chassis of the furnace.. Oh well..

P.P.S.  In the last photo you can see some of the crap that came out when I disassembled the motor -- lots of black crud..

http://tinyurl.com/oph2bf6
Re: Furnace fan motor for mid 80's LD..
Reply #15 –
Yahoo Message Number: 143765
"IF no local shops have a replacement I will see about using some Permatex gasketsealant like that used on engines for various liquids or gas"

Ric k

High-temp RTV silicone should work fine, with careful application..
http://www.autozone.com/autozone/accessories/Permatex-Hi-temp-RTV-silicone-gasket-maker/_/N-25a0?itemIdentifier=526939&_requestid=1060357
 The rear bushing may be a oilite bushing, not a a ball bearing. It would pivot, for alignment but should not spin.

http://en.wikipedia.org/wiki/Oilite

3-in-One electric motor oil is a good choice for lubing the bearings. If the bearing are exposed to high heat, I might consider using synthetic motor oil. The service manual should specify the proper lube..

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Furnace fan motor for mid 80's LD..
Reply #16 –
Yahoo Message Number: 143766
"P.P.S.  In the last photo you can see some of the crap that came out when I disassembled the motor -- lots of black crud..
http://tinyurl.com/oph2bf6"

 Rick

The photo link is dead.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Furnace fan motor for mid 80's LD..
Reply #17 –
Yahoo Message Number: 143767
Thanks Larry.. I will look thru the manual for lube instructions... neither end has a true bearing that spins... I did run it a little with some thick grease I had but will switch to a thinner motor oil per your suggestion..  Without the true bearing this motor will never spin easily.. Which in my mind means that it will consume more power because it takes more oomph  to spin the armature...  I wonder if a new one would spin easier...
Re: Furnace fan motor for mid 80's LD..
Reply #18 –
Yahoo Message Number: 143768
"neither end has a true bearing that spins... I did run it a little with  some thick grease I had but will switch to a thinner motor oil per your  suggestion..  Without the true bearing this motor will never spin  easily."

Rick

Bronze or oilite bushing are true bearings, just a different style. When in good condition, they work fine.
Oilite is made from ground or powered metal, compressed into the final shape,  filled with millions of tiny voids that hold oil. They have been used in electric motors for many decades, long before ball bearing were available, and are still common today.
Heavy grease should not be used with oilite, just straight oil. The soap, in grease, can plug the micro-voids in oillite, restricting its ability to hold and release oil.
 In industrial applications, bronze bushing sometimes become and require heating with a torch, until red hot  to burn out the residue and reestablishing the voids. The bushings are then boil in oil for re-lubrication..
 Since heating isn't an good option, you may be able to clean your bushings with a spray carburetor or brake cleaner. Keep the solvent off the armature's windings to protect the wire's varnish coating.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Furnace fan motor for mid 80's LD..
Reply #20 –
Yahoo Message Number: 143770
Thanks Larry.. More info I did not know!! I will switch it out today for oil and see how it goes..
Re: Furnace fan motor for mid 80's LD..
Reply #21 –
Yahoo Message Number: 143773
Rick, With help from Garry (and a great link), I'm going through the same thing as you this weekend. I opened up the motor end caps, lubricated the bearings, left the armature and associated parts alone, then closed it up and installed it back in the furnace housing. This motor was hard to turn also, but ran fine when I put 12v to it on the bench.
As far as the gasket goes, I used high temp permatex first, then checked that the fans rotated freely, and unfortunately they didn't. So I removed the assembly and cleaned off all the permatex, re-adjusted the centrifugal fan, then put it back together with 1/4" x 3/8" foam sticky back door seal. Much easier than Permatex (should I have to pull it apart again) and should not be affected by any heat at that end. Just installed it back into the LD fired it up, sounded great, then started making a chattering sound like the fan blades came loose off the shaft. I cinched the set screw down as tight as possible, but I'm suspecting it worked its way loose. So, out if comes again today to see what's going on...........ugh.

Jim Brenneke

To: lifewithalazydazerv@yahoogroups.com From: lw5315us@...
 Date: Fri, 22 Nov 2013 23:56:07 -0800
 Subject: RE: Re: [LD] RE: Furnace fan motor for mid 80's LD..

"IF no local shops have a replacement I will see about using some Permatex gasketsealant like that used on engines for various liquids or gas"

Ric k

High-temp RTV silicone should work fine, with careful application..
http://www.autozone.com/autozone/accessories/Permatex-Hi-temp-RTV-silicone-gasket-maker/_/N-25a0?itemIdentifier=526939&_requestid=1060357
 The rear bushing may be a oilite bushing, not a a ball bearing. It would pivot, for alignment but should not spin.

http://en.wikipedia.org/wiki/Oilite

3-in-One electric motor oil is a good choice for lubing the bearings. If the bearing are exposed to high heat, I might consider using synthetic motor oil. The service manual should specify the proper lube..

Larry
Re: Furnace fan motor for mid 80's LD..
Reply #22 –
Yahoo Message Number: 143774
Update, Pulled furnace out, checked fan to see if it came loose, it wasn't. But I bent each blade back towards the motor about a 1/4". These blades can get bent very easily, so I suspect in my disassembly, I tweaked the blades so they were bent down a bit too far towards the burner, for lack of a better explanation. So I just put it back in the LD and fired it up and it purrs like a kitten.......whew!! Thanks again to Garry for the link to removing one of these furnaces.........

Jim Brenneke

To: lifewithalazydazerv@yahoogroups.com From: jbren57@...
 Date: Sat, 23 Nov 2013 13:03:14 -0800
 Subject: RE: [LD] RE: Furnace fan motor for mid 80's LD..

Rick, With help from Garry (and a great link), I'm going through the same thing as you this weekend. I opened up the motor end caps, lubricated the bearings, left the armature and associated parts alone, then closed it up and installed it back in the furnace housing. This motor was hard to turn also, but ran fine when I put 12v to it on the bench.
As far as the gasket goes, I used high temp permatex first, then checked that the fans rotated freely, and unfortunately they didn't. So I removed the assembly and cleaned off all the permatex, re-adjusted the centrifugal fan, then put it back together with 1/4" x 3/8" foam sticky back door seal. Much easier than Permatex (should I have to pull it apart again) and should not be affected by any heat at that end. Just installed it back into the LD fired it up, sounded great, then started making a chattering sound like the fan blades came loose off the shaft. I cinched the set screw down as tight as possible, but I'm suspecting it worked its way loose. So, out if comes again today to see what's going on...........ugh.

Jim Brenneke

To: lifewithalazydazerv@yahoogroups.com From: lw5315us@...
 Date: Fri, 22 Nov 2013 23:56:07 -0800
 Subject: RE: Re: [LD] RE: Furnace fan motor for mid 80's LD..

"IF no local shops have a replacement I will see about using some Permatex gasketsealant like that used on engines for various liquids or gas"

Ric k

High-temp RTV silicone should work fine, with careful application..
http://www.autozone.com/autozone/accessories/Permatex-Hi-temp-RTV-silicone-gasket-maker/_/N-25a0?itemIdentifier=526939&_requestid=1060357
 The rear bushing may be a oilite bushing, not a a ball bearing. It would pivot, for alignment but should not spin.

http://en.wikipedia.org/wiki/Oilite

3-in-One electric motor oil is a good choice for lubing the bearings. If the bearing are exposed to high heat, I might consider using synthetic motor oil. The service manual should specify the proper lube..

Larry
Re: Furnace fan motor for mid 80's LD..
Reply #23 –
Yahoo Message Number: 143777
Sounds good...Jim I had to straighten a couple of blades as well, however I got lucky and noticed them before re-installing everything...
Couple of things these motors have a fair amount of axial slop so after being lubed theu might slide from the fan thurse enough to interfere even if not bent. You sometimes have to play with the position of the fan or squirrel cage a tad.

Garry
Re: Furnace fan motor for mid 80's LD..
Reply #24 –
Yahoo Message Number: 143800
Got ours put all together yesterday as well and at least the squeaky motor is appearing to be fixed..  We are out of propane so I can't yet test the pressure or lighting ability..  I'm hoping to do that today... Still got to fix the coat closet rack that broke last time it was used and about 4 other things b4 tomorrow's departure...