# Too many moving parts on these machines.



## cold front (Jan 31, 2012)

Arrrrrr! now I have to replace the convection fan. There is two sealed bearing on the spindle and one of them is making noise (enough to bother me).  No wonder people sell these after a season or 2.  Good thing I don't mind getting my hands dirty because I have put a lot of time into cleaning, tightening down loose parts, adjusting parts, Replacing a combustion fan and now this!

The convection fan comes apart very easily into its component part..pulled the squirrel cages off and unbolt the engine from the frame.  The sealed bearing must be press onto the spindle some how...too bad I don't know much about this because I bet all I have to do is pop the bearing off and somehow replace them by pressing them onto the spindle.  I wish I took a shop class in high school..it would come in handy now. So I guess I'll have to buy the whole damn unit from the dealer $$$.


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## SmokeyTheBear (Jan 31, 2012)

Shop class what's that?

Folks here might be able to cross reference it if we are provided the numbers on the makers plate starting with the makers name.


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## cold front (Jan 31, 2012)

Oh...also I'm back to burning oil tonight till I can get this fixed......somewhere out there, there is an oil man laughing his butt off!


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## cold front (Jan 31, 2012)

SmokeyTheBear said:
			
		

> Shop class what's that?
> 
> Folks here might be able to cross reference it if we are provided the numbers on the makers plate starting with the makers name.


Hi Smokey, The St. Croix part number for the convection fan unit is 80P20003-R. I might be able to get the bearing part numbers if it's stamped into the side?


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## SmokeyTheBear (Jan 31, 2012)

cold front said:
			
		

> SmokeyTheBear said:
> 
> 
> 
> ...



Sorry, I'm looking for what is on the blower makers plate, cross referencing a possibly missing number because the stove maker tells the actual part maker he can't show it in any cross reference list is usually a losing proposition.

My blowers were like that even though they fit the blower makers numbering scheme.

ETA: Also the bearings may be fine and the fan became unbalanced due to buildup.


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## wwert (Jan 31, 2012)

Try some Teflon spray lube on the bearings, may save the day.


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## cold front (Jan 31, 2012)

The Motor part number is J238-200-2040 (115v 60hz 1.6A) (T.P.L CL.F) (RU)

Bearings: Thailand NMB 608S

The problem may be with the motor armature, It looks a bit beat up and the bearings feel smooth when I spin them by hand.


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## ohbix (Jan 31, 2012)

Even if you get a new fan, suggest you try replacing the bearings and keep the fan as a backup.  My bixby convection fan is prone to bearing noise.  Replace them and life is good.  The bearings seemed fine, but were the noise source.


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## SmokeyTheBear (Jan 31, 2012)

Granger carries a pile of bearings they should be able to cross that NMB 608S bearing into the line they carry.

There are also a large number of places on line that sell bearings and it is a common bearing size. 

That doesn't look all that banged up.  I'd get the bearings and do a replacement.

That particular setup is very difficult to cross.

ETA: For no shop class you did a good job getting it apart.


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## nailed_nailer (Jan 31, 2012)

If the bearing is pressed on you can remove them by slightly reducing the shaft size and increasing the bearing size.

Usually if you apply cold temps to the shaft alone it will shrink slightly.
Dry Ice or Liquid nitrogen should work.
You can get Nitrogen in one of those freeze cans at an electronics supplier.
If you hold the can upside down the liquid should be cold enough to shrink the shaft.
Try to not get the bearing cold.
The bearing should pull right off.

Replacement bearings are available almost anywhere
Here is one place (there are many)
http://www.mcmaster.com/#standard-ball-and-roller-bearings/=g1n6w6

Replacement is easy.
Heat bearing with hair dryer and slide it onto shaft.

Good Luck,
---Nailer---


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## cold front (Jan 31, 2012)

Does the wear on the armature look ok?  I am really not sure if the sound is coming from the bearings...you can't spin them fast enough by hand or drill. The is  coming from the unit though.


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## SmokeyTheBear (Jan 31, 2012)

Be certain to not get your bare hands in the coolant.  Bad, very bad if you do.


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## SmokeyTheBear (Jan 31, 2012)

You could clean it all up put it back together and test it.


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## wil lanfear (Jan 31, 2012)

608 series bearings are used on skateboard wheels, many to choose from, I purchased some that are sealed off ebay.

http://www.ebay.com/sch/i.html?_fro...skateboard+bearings&_sacat=See-All-Categories


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## SmokeyTheBear (Jan 31, 2012)

http://www.grainger.com/Grainger/ww...ring&op=search&Ntt=608+bearing&N=0&sst=subset


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## mralias (Jan 31, 2012)

cold front said:
			
		

> Does the wear on the armature look ok?  I am really not sure if the sound is coming from the bearings...you can't spin them fast enough by hand or drill. The is  coming from the unit though.



That shinny side looks like it might be rubing against something. Looks uneven to me. Not that it helps at all but you may be right. Might not be the bearings.


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## SmokeyTheBear (Jan 31, 2012)

Small pieces of pellets or such sometimes can get into the works, I'd clean it all up reassemble it checking all clearances as I went and take it for a test drive on the bench first.


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## cold front (Jan 31, 2012)

cleaned everything put in back in and same problem.  I took it apart again and I'm pretty sure its the right bearing.  Talk to the dealer, he's a real good guy.  He told me they just replace the whole unit and never break in down like I did.  You need a press to get the bearing off, you can cool it down but it's hard to keep it to the shaft only he said.

The only way I could tell which bearing it was, was to hold the spindle in one hand and pinch the bearing in the other hand between my thumb and index finger then, turn the spindle back and forth.  This way you can actually feel the little balls catching on the bad bearing.  

In a way this stove machine has been like a shop teacher to me (along with this board of course). I have learned a lot.  I think a shop class or two should be mandatory in high school even if you're not going into the skilled trades you would gain skills that could help you the rest of your life.

Smokey, Thanks for the heads up on the coolant. I was wondering what the copper tubes were for on the motor.  

Thanks to all.


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## SmokeyTheBear (Jan 31, 2012)

cold front said:
			
		

> cleaned everything put in back in and same problem.  I took it apart again and I'm pretty sure its the right bearing.  Talk to the dealer, he's a real good guy.  He told me they just replace the whole unit and never break in down like I did.  You need a press to get the bearing off, you can cool it down but it's hard to keep it to the shaft only he said.
> 
> The only way I could tell which bearing it was, was to hold the spindle in one hand and pinch the bearing in the other hand between my thumb and index finger then, turn the spindle back and forth.  This way you can actually feel the little balls catching on the bad bearing.
> 
> ...



The coolant I was concerned about was what nailer was suggesting would  shrink the shaft so you could get the bearing off easier.  That stuff is down right flesh freezing cold.

Spending a lot of time with a good millwright beats any dozen high school shop classes and a lot of college engineering programs.


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## ironpony (Jan 31, 2012)

sometimes using a small pick/awl
you can lift out the side seal on the bearing and add grease
then snap the seal back in
at this point you have nothing to loose

get a replacement coming and this might keep it going until the replacement arrives

when my combustion blower failed after 15 years
I added drops of oil daily until my replacement arrived

you can also cut off the old bearing with a dremel and cut off wheel
then probably tap the new one on using a piece of pipe over the shaft to keep it square

there is more than one way to skin a cat


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## SmokeyTheBear (Jan 31, 2012)

Cat skinning is a capital crime in this household, that is what his royal majesty has decreed so be very careful.


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## cold front (Jan 31, 2012)

Yup, the Dremel with cut off wheel made very short work of it.  I think the Dremel might replace the crowbar as my most favorite tool.

So, now i'll order up the bearings and figure out how to press them on...I'm thinking a small cooper pipe to fit over the spindle and a vice.


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## wil lanfear (Jan 31, 2012)

If your not comfortable replacing the bearings yourself, take it to the local tech center or high school that has a program that relates to relacing the bearings, I'm sure they would do it for you. I've had my local tech center do many things for me. Another option, take it to a local machine shop. Heck of a lot less expensive replacing both bearings vs a brand new blower.

EDIT: Now that you got the bearings off, make sure when the new bearings are installed, the pipe that is used only touches the inner race of the bearing, not the seal or outer race.


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## krooser (Jan 31, 2012)

Put the armature into your freezer for a few hours... it will shrink the shaft and allow you to get the bearing on easier.


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## turbotech (Feb 5, 2012)

How old is this fan assembly?

You can use a pick to remove the rubber seals to see what went bad with the bearing. Probably a little dust worked in past the seals. Adding grease will get you by for a limited amount of time. The problem is at this point the bearing is really done and will make a lot of noise.

Replacing with a loose tolerance (heat expansion), low noise bearing is the best bet. At $3 each from an NMB source is best. Don't put in the low grade Ebay or other source bearing. It will be noisy and probably won't last in this application.......and they also do a 3x markup on price of a lower quality than NMB bearing.

Apline Bearing sells the NMB 608S for $3 each but there is a min. of $15 purchase. Try contacting them and let them know what the application is.


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## CTYank (Feb 5, 2012)

cold front said:
			
		

> Yup, the Dremel with cut off wheel made very short work of it.  I think the Dremel might replace the crowbar as my most favorite tool.
> 
> So, now i'll order up the bearings and figure out how to press them on...I'm thinking a small cooper pipe to fit over the spindle and a vice.



For any automotive machine shop, pressing such a bearing on is a trivial task.


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## cold front (Feb 5, 2012)

After I cut the bearings off I inspected them the best I could.  There was plenty of grease in both.  There is a metal strip like part inside that hold or cradle the balls around the race of the bearing.  One of the balls had somehow broke the metal strip cradling it. I think this is where the noise was coming from. If I can't press it on myself after putting it in the freezer a while I'll take it to a shop.


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## cold front (Feb 5, 2012)

turbotech said:
			
		

> How old is this fan assembly?
> 
> You can use a pick to remove the rubber seals to see what went bad with the bearing. Probably a little dust worked in past the seals. Adding grease will get you by for a limited amount of time. The problem is at this point the bearing is really done and will make a lot of noise.
> 
> ...



The fan assembly was in operation for 4 years.  The stove is a work-horse, it heats the whole house about 1200 ft2.  This may have something to do with all the parts failure I have had after the 3-4 year mark.


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## Snowy Rivers (Feb 5, 2012)

Here is a tid bit that you can think about.

If you can spin the shaft and the thing is quiet, then the likely cause of the noise is not the bearings.

Try wiring the fan up to a "patch cord" and plugging it directly into a 120V outlet.
Be careful with the live POWER

First blow out the squirrel cage fans and or better yet, wash them in a sink full of warm soapy water using a small brush to carefully clean all the blades.

Once done, try running it, and if its quiet, put it back in the stove.

Now, if the noise resumes, its not the bearings, but instead, harmonics that are setting up in the armature due to the power flow from the Triac speed controller.

If the Triac is not sending a perfect (or nearly so) "chopped" wave form to the motor, the armature will/can start to emit a whinning or some such noise.

As mentioned, out of ballance, due to dirt build up in the fan blade can also cause bad vibes.

If a bearing is bad, it will almost always feel rough and make noise when spun.

Packing more grease into the bearings and or changing the bearings may stop the noise, BUT this change can simply disguise or dampen the harmonics caused by a flakey Triac, and may return in a short while.

My Whitfield Advantage 2 has a "sweet spot" that the fan runs well and makes just air noises, if I move the speed controller very much away from that spot, it starts making noise in the form of a whinning, and is quite anoying.

This sort of noise can be very anoying, especially if the stove is in a room that you spend time in, watching TV or other things that you dont want to listen to some odd repetitious noise.

Give this a go and see what shakes.

Snowy


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## turbotech (Feb 9, 2012)

The description of noise makes me think the bearings are the problem.
Did you get some 608S  (low noise) replacements?
Got them installed yet?

What are the other failures you have had at the 4 yr mark?


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## chamas (Feb 10, 2012)

Snowy Rivers said:
			
		

> If the Triac is not sending a perfect (or nearly so) "chopped" wave form to the motor, the armature will/can start to emit a whinning or some such noise.


Interesting. So the easy way to test the triac is to run the motor/fan assy without the triac and see if the whining noise disappears? And if so, replace the triac?


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## cold front (Feb 10, 2012)

Triac speed controller. Thanks this is very good to know because I'm sure that will fail next if it has not already. 

I replace the whole fan unit with a new one and I don't seem to have the noise problem anymore.  I also got bearings replacements for the old unit and have not tried yet to pop them on the spindle.  From what I can tell it's not easy.

Here is a list of things that have gone wrong with my  St. Croix Prescott:

1) The decorative masonry brick fell apart in the second season.
2) The combustion blow failed at the end 3rd season.
3) The cam connector rod on the versa grate loosened up twice in the middle of the 3rd season.  It made a clunking noise and the versa grate was only half working. Tightening down the inset screws on the rod with thread lock fixed it.
4) The screws holding the control board to the control board mount box came loose and the board fell into the box at the beginning of the 4th season.  Screwing the board back into the mount with thread lock fixed the problem.
5) The convection fan unit failed in the middle of the 4th season (this season).


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## turbotech (Feb 12, 2012)

Older control boards have more primitive TRIAC designs that are more susceptible to making motor noise. What usually destroys a TRIAC is a stuck motor due to bad bearings. The bearings start to seize or seize completely. This causes the current to go up and destroy the TRIAC. A TRIAC rarely ever gets "worn out".

The best way to put the bearings on the shaft is to use a shop press. Next best is a large bench vise. You could also make a small press out of 2 pieces of threaded rod and angle iron. All you would need is a drill to make the threaded rod holes and hole to fit over the shaft.


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## slls (Feb 12, 2012)

I would use a piece of tubing.


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## turbotech (Feb 12, 2012)

Yes, all of the methods require a piece of tubing to place against the inner race so that the seal and outer race are untouched. Hit the seal at all and the bearing is junk....it will be loud. The 608S MT should have seals that are extremely quiet and don't touch anything internally.


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## woodsman23 (Jan 10, 2013)

I had an issue with my afton bay last night with a dry bearing, i took it all apart and olied the bearings and all is well once again. can anyone let me know if there is a cross reference # for the 608 replavement bearing at grainger?


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## CT Pellet (Jan 10, 2013)

_"Too many moving parts on these things."_
If you think "moving parts" is a problem, wait until them parts DON"T move! Now that's gunna be a bltch!


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## woodsman23 (Jan 10, 2013)

CT Pellet said:


> _"Too many moving parts on these things."_
> If you think "moving parts" is a problem, wait until them parts DON"T move! Now that's gunna be a bltch!


 
been there  done that


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## Bioburner (Jan 10, 2013)

The 608 is a very, very common bearing. Bring in to NAPA or good automotive supply, alternator or starter repair shop. Please do not use skateboard bearings.They do not have a very good load factor.(Probably no grease just light oil if lucky) You get what you pay for. Japanese or German bearings top quality. I won't put my time or life on less quality.


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## Harvey Schneider (Jan 10, 2013)

cold front said:


> The problem may be with the motor armature, It looks a bit beat up and the bearings feel smooth when I spin them by hand.


Just an observation. When you see scuff marks on the armature it is usually because one of the bearings is not holding the shaft on center. That happens either due to a failed race or the motor's end cap is loose.


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## Mr. Spock (Jan 10, 2013)

If you don't have a press, I have successfully seating a bearing using the pipe method others have mentioned. It's a bit more medieval then using a press but it can be done. Find a pipe with the same diameter as the inner race that will fit over the spindle. Tap the pipe with a hammer. In a jam I have used brass rounds and tapped on the inner race moving around the race circumference. Need a steady hand though...don't want to hit the bearing seal.


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## Xena (Jan 10, 2013)

cold front said:


> Arrrrrr! now I have to replace the convection fan.
> No wonder people sell these after a season or 2.


 
People who don't learn the ropes might end up selling after a season or two...
The blowers need to be removed and cleaned and stove needs to be cleaned
properly. I learned the lesson the same way you did.
I'm in 8th year with my Prescott and it's a heat monster that works fantastic
with the right maintenance.


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## Montnl (Jan 10, 2013)

See this,

Blower Bearings
Original Bearings,  608SSD21.  Interior Diameter – 0.315” (8 mm). Exterior Diameter – 0.8661” (22 mm). width – 0.276” (7 mm). Grease Lubrication
BRAND 
PART NUMBER 
MATERIAL OF CONST 
LUBRICATION 
WHERE TO BUY 
TEMPERATURE RANGE 
PRICE
Dayton 
1ZFF5 
Steel 
Oil Lube 
Grainger 


SKF 
608-2RSL 
Steel 
Oil Lube 



TIMKEN 
38 KDD 

Oil Lube 

0 – 250 °F 

FREUD 
62-108 

High Temp Grease 

0 – 250 °F 
$5.45, routerbitworld.com
McMaster Carr 
6153K71 
SS400 
Grease 

-40 – 300 °F 
$13.54
ACE 
608 

Grease 
ACE 

$10.00

My choice is MacMaster Carr or Freud. Freud bearing is designed for router bit use, high speed and temperatures, tough use.
Do not buy roller skate bearing from ACE or you local hardware store unless you want to change bearing more often. And do not use Oil lube bearings, they are designed to have oil at all times.


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## Montnl (Jan 10, 2013)

Sorry, the table did not post right.


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## Montnl (Jan 10, 2013)

Here is as .pdf file


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## ChandlerR (Jan 10, 2013)

You guys rock. I read the post and every suggestion I had was talked about.  The biggest thing is to not drive the bearing on by anything other than the inner race. The very best way would be to press them on with a hand press. I like the idea of putting the armature in the freezer and maybe heating the bearings up with a hair dryer.  They may slip right on by hand.  I use a neat tool called an induction heater at work. It amazes me every time I do bearings that bearings can be heated without heat


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## jlupi (Jan 10, 2013)

vid on cleaning sealed bearings


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## jlupi (Jan 11, 2013)

ironpony said:


> ide seal on the bearing and add grease





ironpony said:


> sometimes using a small pick/awl
> you can lift out the side seal on the bearing and add grease
> then snap the seal back in
> at this point you have nothing to loose
> ...


 

grease or oil?


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## Harvey Schneider (Jan 11, 2013)

jlupi said:


> grease or oil?


Grease for low speed, oil for high speed.


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## rona (Jan 11, 2013)

cold front said:


> The Motor part number is J238-200-2040 (115v 60hz 1.6A) (T.P.L CL.F) (RU)
> 
> Bearings: Thailand NMB 608S
> 
> The problem may be with the motor armature, It looks a bit beat up and the bearings feel smooth when I spin them by hand.


 They can feel smooth at a low rpm such as spinning by hand but  it is a common problem on Bixbys and when you spin by hand they seem fine  but put new ones in and it runs like new.


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## vetteandharley (May 16, 2014)

cold front said:


> Arrrrrr! now I have to replace the convection fan. There is two sealed bearing on the spindle and one of them is making noise (enough to bother me).  No wonder people sell these after a season or 2.  Good thing I don't mind getting my hands dirty because I have put a lot of time into cleaning, tightening down loose parts, adjusting parts, Replacing a combustion fan and now this!
> 
> The convection fan comes apart very easily into its component part..pulled the squirrel cages off and unbolt the engine from the frame.  The sealed bearing must be press onto the spindle some how...too bad I don't know much about this because I bet all I have to do is pop the bearing off and somehow replace them by pressing them onto the spindle.  I wish I took a shop class in high school..it would come in handy now. So I guess I'll have to buy the whole damn unit from the dealer $$$.


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## vetteandharley (May 16, 2014)

Hate to bring up an old post but how do you remove the squirrel cages on this particular convection fan?  St Croix Auburn stove. Thanks


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## stash (Oct 14, 2015)

cold front said:


> Hi Smokey, The St. Croix part number for the convection fan unit is 80P20003-R. I might be able to get the bearing part numbers if it's stamped into the side?


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