How to replace a blower bearing
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- Опубликовано: 28 авг 2024
- This one is a continuation of a blower bearing failure and replacement. This video is part of the heating and cooling series of training videos made to accompany my websites: www.graycoolingman.com and www.grayfurnaceman.com to pass on what I have learned in many years of service and repair. If you have suggestions or comments they are welcome.
If you are a homeowner looking to repair your own appliance, understand that the voltages can be lethal, the fuels are highly flammable and high pressures are used. Know your limits.
I utilized your method for replacing my bearings. Got the bearing kit from Grainger in 2 days. Got a new shaft cut from my local metal supply store. I probably have 2 hours into the whole repair. Including removing the blower assembly to facilitate repair the reassembly. It's video's like yours that make DIY home repairs possible.
Glad it helped.
GFM
Very nice having a great workbench to do this work.
All the best.
I got a pair of the same so-called "bearings" with the rubber sleeves from the local hardware store for an old blower I'm repurposing for something else. I'm glad I watched your video because I was wondering why the hell the new bearings were solid (The center brass collar wouldn't spin within the bearing.... I've changed hundreds of ball bearings on the farm on equipment over the years, But I never seen one so stiff as these blower motor bearings 😂 Then I seen you mention that they are bushings, as I was kind of thinking maybe that's all they are? I just thought that it would wear very quickly if they didn't have an actual ball bearing, but at least now I know 👍 It seems quite misleading that they call them bearings when in reality they are truly just bushings 🤷♂️
After 52 years, the pulley side bearing on my squirrel cage blower is worn. The shaft on that side has perpendicular play and the blower is noisy. The bearings are like the ones your video shiws and have no oil cups. I oiled annually over the past 25 years with drops right where the shaft runs into the sintered bronze sleeve. That only the pulley side is worn tells me it was likely belt tension, plus it's a bit harder to oil that side because of the pulley.
I have found what look like exact replacement bearings ($50 each) - they do have oil cups and the bearing cage on the blower housing is drilled for them. The whole blower assy is $300 plus part.
One of the mysteries to me is what centers the shaft from side to side.
The non pulley side of the shaft is grooved near the end, but there was never any thrust washer, or circlip installed. The pulley could act as a stop in one direction, but didn't seem to, as the shaft has limited lateral play, but not enough for the squirrel cage to hit the housing and with no clear indication of what is laterally locating it (other then the pulley - in one direction).
The shaft is .75 in diameter at the ends. I haven't been able to measure if it is .75 in for it's full length - a step up in diameter would laterally locate the shaft.
The three armed bearing spiders are spot welded to the housing. And the bearing cage is also made up of spot welded pieces - similar to your video. The way the parts are formed, the very edges of the bearing cage are curved inwards towards the blower housing. This seems to suggest that the bearing with it's rubber outer sleeve needs to be pressed out towards the interior of the housing and the replacement pressed in from inside the housing towards the outside.
It's blizzard conditions out! And very fortunately, I was able to silence the blower by installing a thrust washer - held in place by a round wire spring hose clamp - on the non pulley side of the shaft. The blower has run fairly smooth / quiet for almost a week - with the shaft pulled in that direction - but who knows for how long.
It is a shame the three armed bearing spiders were not screwed to the housing - it would have made replacement much easier.
Amazing details 😂
This man is old school
im a plumber-pipefitter-hvac tech , the older stuff the better my friend . this new stuff coming out the past 15 years and especially the past 3 is pure JUNK WOW ,
My furnace is a 1960's Beach Foundry electric furnace and still runs great !
Thanks a lot for the reply I just got my furnace andback together it's purring like a kitten great video and thanks for the link for the barrings
sweet bearing replacement setup...nice work
Thanks for the support.
GFM
I have a building full of 1986 Magic Aire Chilled water units using this type blower assembly. They have held up pretty well for their age but they are quite a pain to work on. Fortunately (for me) the drain pans are starting to rot thru and the owner is looking at replacements now
Thank you for sharing your knowledge!
Welcome
GFM
thank you, it's amazing how durable these blowers are ...
What is the model of the blower fan assembly? Mine looks exactly the same but is all rusted and old and cannot find any writing on it...
excellent video, very educational ... take the opportunity to make an inquiry regarding the tension of the belt or band, which is what you recommend?
great job,, will last very long,,, your right the shaft isnt long enough fot pully
Another great video, THANKS FRIEND
Ronald Cach welcome
GFM
My question is how you meas😮ure for what bearing size when replacing bearing. Also how do you replace fan that is in housing . Also , what determines weather shaft is reusable or not ?Thank you
Another Great Video.... also how tight should this belt be ??? and what is to tight???
Did you clean off the black marks on the shaft and with what fine sandpaper or scotch brite or steel wool and do you put a little oil on it before putting the bearing on??? Please help thanks!
What is the size of the hp in these moter
Learn a lot from your video. Thank you. I have a couple of questions.
When you change the bronze bearing to a ball bearing or roller bearing is it
just the bore and outside diameter you care about? As long as it fits in the
bearing holder? how often do you grease it ? Many thanks.
The inner diameter is for the shaft and the outer is for the bearing holder. Nothing else is important. These bearings are permanently lubricated.
GFM
So if the blower bearing of furnace seems to make noise should it be replcae quickly or still can lasts a few.mor years?
Replace it now.
GFM
Does this have any effects with the blower motor in my furnace that was replace 11 years ago, because last time the heat guy came to check and say our furnace is fine?
Do you think you really need the rubber on the outside of the bearings? I just did my fan and there was no room for the rubbers, the bearings fit perfect without them.
The rubber mounts are there to reduce noise. If it works ok, go for it.
GFM
Great video. Indeed, the fan looks 'cheapo' as you say but it runs amazingly well after the bearing replacement. Well done. Why are you not happy with the aluminum pulley? Do you feel like this will be the component that will fail eventually?
Aluminum pulleys have given me a lot of problems. The drivers wear out too soon and break. The driven tend to wobble because the aluminum is not so good at holding the set screw.
GFM
grayfurnaceman It's not like you're running a piece of farm equipment with that pulley, just an air pump with little resistance. I've seen and had aluminum pullies on lau and delhi blowers and they seem to hold up just fine after 30 or more years of use. I'm not an HVAC tech, but I have had a few scrapped blowers in my possession. The only time I've seen an aluminum pulley come under the circumstance you have described was when I made a walk behind leaf blower with an old furnace fan, and it was powered by a 5 hp engine and running twice the rotational speed than it was originally specified to do.
bolt/screw better than crappy spot weld = also replaceable.
So without that flat spot the bearing and shaft will jam?
The flat on the shaft is for the set screw that holds the blower wheel and driven pulley.
GFM
So I was wondering, does the blower bearings and blower motor both have affects on the furnace to operate, since when my furnace runs during the Fall/winter it seems to be making an unusual noise, but when the Central AC Runs during Summer , i felt there isn't any unusual noise?
I think it's because your heater blower uses a different speed than the a/c blower
hey, i’m wondering I have a very old furnace fan. Where do I get bearings like that?
Try a bearing shop or HVAC supply.
GFM
Is this job best left to a hvac pro since it might seems risky for diy and a handyman?
This job is pretty straightforward and can be done by anyone with mechanical skills.
GFM
nice rebuilt
Are rumbly bearings on these units a danger, or just noise nuisance? A neighbor's furnace sounds like this... I'm aware that things should be fixed, but how urgent an issue is this?
I have seen them run for many years. Or just few weeks.
GFM
I am having trouble with my propane furnace it is a American Standard new in 2014. It has just barely started acting up. Right as the blower kicks on it has a sputtering/ rattling sound for about 2 seconds once the blower is on there is no noise. The rattle/sputter is not very loud but it is there. It heats good and everything seems to be working fine. For the past three years there has been no noise at all and this is something new. I want to know if this is something like a cracked heat exchanger and should I worry about leaking harmful fumes any help would be greatly appreciated.
If the noise is only on startup, the blower wheel may be falling apart.
GFM
grayfurnaceman Thank you for the reply. I will be inspecting the wheel tomorrow
Great Video Where did you get the Bearing, I have the exact same unit?
You can usually find them at a bearing store.
GFM
@@hristofiziev9401 don't work locking collier only locks to shaft while shaft spins freely in bearing
Do you have the bearing number used? Also, is it possible to convert a belt driven fan system with a direct drive fan? If so, how would a person reconcile the wiring from the multi speed motor to the old 2 wire belt fan?
If you want to replace the bearings, contact a a bearing store and they can match them up. The only way to convert practically, would be to replace the entire blower with a direct drive one. When you get to the wiring, it depends on the individual situation.
GFM
@@grayfurnaceman I have a direct drive blower complete, so would I just pick the wire matching the one speed I want? Then trial and error for the speed to fit my situation, like starting with medium speed.
@@donens9310 Be sure you know which is common or the motor will burn up.
GFM
@@grayfurnaceman Thanks for the help!
depends on space for the most part , but direct drive blowers are inferior to belt driven ones.
Can you please give me the part# to the complete blower
There is no one part #. I would take the old bearings in to a bearing store and ask them to match up with ball bearings.
GFM
My Fan Motor condenser RPM 825 was burnt, can I change RPM 1075?
Tried that on a Rheem furnace. The 1075 motor overdrew amps.
GFM
Does it needs safety?
Other than simple precautions when using tools, no.
GFM
Is that bearing a UC205-16? If not what is it?
I don't have a part #.
GFM
Bearing number
Raber damper out
where is the squirrel that goes in the squirrel cage!!!?
I imagine the pulley side bearing is the usual suspect
Thanks for tips. I have bearing problems all the time. It's leaking the oil. Your new bearing looks better than original bearing. Where and how can I get it? And can I have the part number and brand? The original bearing I replaced is Delhi 67-4136-2. I live in Ontario Canada.
The bearing used was purchased from a local bearing supply. Just bring your bearing in and have them match it with a ball bearing assembly.
GFM
i see. bearing supply? Can you give me the name of supply if you don't mind? And one more question. Your pulley and mine is opposite. Is there any difference? My pulley must hit the bearing itself that's why it is leaking I guess. Am I right?
I used Brown bearing supply. Not sure if it is in multiple cities. There should not be any difference.
GFM
Thanks
Jaeho Lee There's a place in Niagara called Canadian Bearing - I've used them for many things - they have everything from basic ball bearings to ceramic and frictionless. A great shop to deal with. Another great shop - Bocca Bearings - both have websites.
LMAO 🤣 why not just buy the right bearing for the blower assembly instead of hacking it to pieces.
There are several reasons.
If your shaft is damaged (most are), the shaft will have to be replaced. Sometimes not a simple changeout as the new shaft will have to have flats filed in it.
Using ball bearings eliminate seasonal oiling. Probably the reason the old bearings failed. Ball bearings generally last longer.
Ball bearings can be used on most damaged shafts.
Finding the correct bearings can be a challenge.
GFM
You know they make a $20 tool that can do this same task better in less time with no welding or rigging... As a professional HVAC instructor and tech I would recommend some troubleshooting classes and using the right tool for the job. Work smart not hard bubba.