Today my furnace fan started screaming like a banshee on startup. It howls for a few seconds then quiets down.I know I need to pull it apart and lube the bearings, if equipped, or otherwise effect a repair to it.I'm amazed it lasted this long without groaning in protest at my over-use of it. Anyhow, I need to pull the fan out and service the thing. I have never had one of these things apart before. Anyone know if it has bearings or bushings?Do I go at it from the inside or the outside? Do I have to pull the furnace out to do it? I haven't even looked at it yet aside from a sideways glance as I walked by on my way to the potty room.I have good access to it from the top too, by removing a piece of plywood in the lower bunk to expose the furnace, HWT and water pump.Maybe it just needs another pound of butter........It is an Atwood Excalibur 8500-III hydro flame - 1997 model.Thanks.

When mine sang to me it turned out to be the "squirrel cage" type thing (hamster wheel looking thing) had broke lose from the shaft.Sorry I can't answer your question as to how easy. RV was parked on lot and call RV guy to have fixed by following weekend. So it was pretty easy for me.

All you have to do is follow the installation procedure in reverse. Not a smart a$$ answer, just what I read in an Atwood manual. If you do not have the installation manual, you can download it from Atwood. The odds are that it has bushings and while putting some oil on the bushings may help for awhile, you will need a new motor.The tech that replaced mine (a Suburban) said the worse part of the work is removing the squirrel cages from the motor shaft.

If you haven't done so already, try some creative ways to get some lube in there before you pull it out. I've used long tubes of the diameter of those on sewing machine oil (which works like a dream, BTW), specially bent lengths of coat hanger with q-tips taped to the ends and even a length of broom straw dipped in oil. This has given me years of extra service on fans from those that are seldom used to ones that work for hours a day.

It is not at all hard- no need to remove the furnace at all. From the outside, remove the circuit board, black plastic fan shroud (remove fan relay to help), large squirrel cage (1/8" allen wrench), small squirrel cage (long 1/8" allen wrench through the hole in the cover), loosen bracket, pull motor (I leave the small squirrel cage in the housing and pull the motor out from it). Takes me around a half hour.The bearings are sleeve type, permanently lubed (!). If the shaft is wobbly (and has worn), you must replace it. If it is just dry, replacement is recommended, but I have drilled a small hole in the bell end to add oil. One time I installed a new motor, had it start to squeal after a single day, so I oiled the old one (customer was leaving for the summer before i could get a replacement). It lasted most of a year until they returned the following fall.

A friend and I pulled their furnace out last year. At the start of the season he installed the batteries in reverse polarity and blew the board. (oops)If you have to pull it right out, easy to get out. You should install a plug for the end of the gas line to cap it off until you are ready to re-install it. If you have to disconnect wires, there's a few in there that can be confusing. We made a detailed diagram (I thought), but when we went to reconnect it, something didn't seem right and I had to make up an extra wire with a connector. His kid may have walked off with a piece of wire, we just don't know. Taking a few photos may help as you disconnect things if you're taking a bunch of it apart.We had to pull off the exterior vent cover to get the furnace out on his. They use a type of putty to seal it to the wall so you should get some new stuff for re-installation.Getting it back in was a bit of a PITA as something kept hanging up on the enclosure. Getting the gas line tightened up again was hard to reach in. Unless you are confident with connecting gas fittings, I would get a bottle of gas leak detector to make sure it's a tight seal. If it doesn't fire up at first, there could be air in the line you'll need to purge. Opening a burner on the stove and getting it to light should do it.As above, maybe you can just do it without pulling it right out and then you can ignore what I said.If the fan assembly needs to be replaced, I'd suggest buying one online if you can wait. A local RV dealer will cost you a small fortune in comparison.Otherwise, it's pretty simple. As per Haynes manual, installation is reverse of removal.

How easy to pull furnace fan out? | Good Sam Community

Chris_Bryant
Explorer II
Feb 18, 2014
It is not at all hard- no need to remove the furnace at all. From the outside, remove the circuit board, black plastic fan shroud (remove fan relay to help), large squirrel cage (1/8" allen wrench), small squirrel cage (long 1/8" allen wrench through the hole in the cover), loosen bracket, pull motor (I leave the small squirrel cage in the housing and pull the motor out from it). Takes me around a half hour.

The bearings are sleeve type, permanently lubed (!). If the shaft is wobbly (and has worn), you must replace it. If it is just dry, replacement is recommended, but I have drilled a small hole in the bell end to add oil. One time I installed a new motor, had it start to squeal after a single day, so I oiled the old one (customer was leaving for the summer before i could get a replacement). It lasted most of a year until they returned the following fall.
sum1
Explorer
Feb 18, 2014
If you haven't done so already, try some creative ways to get some lube in there before you pull it out. I've used long tubes of the diameter of those on sewing machine oil (which works like a dream, BTW), specially bent lengths of coat hanger with q-tips taped to the ends and even a length of broom straw dipped in oil. This has given me years of extra service on fans from those that are seldom used to ones that work for hours a day.
D_E_Bishop
Explorer
Feb 18, 2014
All you have to do is follow the installation procedure in reverse. Not a smart a$$ answer, just what I read in an Atwood manual. If you do not have the installation manual, you can download it from Atwood. The odds are that it has bushings and while putting some oil on the bushings may help for awhile, you will need a new motor.

The tech that replaced mine (a Suburban) said the worse part of the work is removing the squirrel cages from the motor shaft.
path1
Explorer
Feb 18, 2014
When mine sang to me it turned out to be the "squirrel cage" type thing (hamster wheel looking thing) had broke lose from the shaft.
Sorry I can't answer your question as to how easy. RV was parked on lot and call RV guy to have fixed by following weekend. So it was pretty easy for me.

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