# Impeller bearing question.



## WrenchIt (Dec 6, 2020)

I just removed the old bearing from my HS828's impeller (blower) shaft. The new bearing seems to be a fairly loose fit on that same shaft. Yes, it is the correct bearing, and the old one, too, was also a loose fit. There was only light rust on the shaft - about three minutes of sanding with very fine sandpaper took care of it. The old bearing was not locked - it was simply noisy indicating it has run dry. Absent a frozen bearing or extended rust, I assume the loose fit is what Honda intended. Is this correct?


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## orangputeh (Nov 24, 2016)

WrenchIt said:


> I just removed the old bearing from my HS828's impeller (blower) shaft. The new bearing seems to be a fairly loose fit on that same shaft. Yes, it is the correct bearing, and the old one, too, was also a loose fit. There was only light rust on the shaft - about three minutes of sanding with very fine sandpaper took care of it. The old bearing was not locked - it was simply noisy indicating it has run dry. Absent a frozen bearing or extended rust, I assume the loose fit is what Honda intended. Is this correct?


should not be a loose fit. impeller bearing for impeller should be 6004UU and the number should be on rubber seals.


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## crazzywolfie (Jun 2, 2014)

if the old one fits better and there is only rubber seals on the sides you could always just pop the seals out and grease them. that would help quiet it down.


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## orangputeh (Nov 24, 2016)

on an impeller bearing you want a perfect fit. to me it's a critical part.


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## JLawrence08648 (Jan 15, 2017)

orangputeh said:


> should not be a loose fit. impeller bearing for impeller should be 6004UU and the number should be on rubber seals.
> 
> 
> > Orangeputeh - you are so good with Hondas! What don't you know about them. I love Honda engines, and Kawasaki, never had a 2 stage Honda to work on, only single stage Hondas.


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## WrenchIt (Dec 6, 2020)

orangputeh said:


> should not be a loose fit. impeller bearing for impeller should be 6004UU and the number should be on rubber seals.


This is the original bearing that came on this machine when I bought it new. There appears to be no wear on the shaft, but there is a raised bump - like a ring around the shaft close to the impeller. When I slip the old (or new) bearing (new one is indeed 6004uu) on the shaft, it hits that bump and rides over it but i can wobble it since there is no raised section for the full thickness of the bearing. I'll try to take a picture of it tomorrow and post it along w/ some measurements.


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## cpchriste (Jan 19, 2014)

I'd suggest a retaining compound. Sounds like a little fretting wear.
www.machinebuilding.net/why-use-a-retaining-compound


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## Arcticnorth (Nov 27, 2020)

I changed the impeller bearing on a 10 year old HS970. It was a perfectly tight fit, and there was no raised bump on the shaft.


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## gpguy2008 (Sep 27, 2020)

Take a Center lunch and make 4 or 8 marks ( depending on how loose it is) equal distance around the shaft where the bearing rides. This will raise the metal slightly at each punch location. Clean everything (including inside the bearing) with alcohol or Brakleen. Install
Using Locktite Bearing Mount ( can’t remember product #). Reassemble and let dry. I’ve seen this used on large equipment as a last ditch effort before MAJOR disassembly and machining. Odds of it working on a snowblower are very good.


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## Oneacer (Jan 3, 2011)

@cpchriste,

Good reading ... thanks ... just put some in my cart.


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## 140278 (Aug 27, 2020)

i can see placing a few indents from a center punch, bearing lock NO . if that new bearing fails you will have issues getting it back off the shaft,
another ?,how many people bother to very carefully remove the seals on a new bearing and see a near total lack of grease? every bearing I have checked for a long time lack enough grease to even lube them self's for a day never mind a life time. now i pop the seals and hand pack reinstall the seals before installing,


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## JLawrence08648 (Jan 15, 2017)

Bearings never have grease in them if you call the amount in them grease. I always remove the seals and grease using synthetic.


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## 140278 (Aug 27, 2020)

tiny dab of clear silicon grease is all i ever see, what's there isn't enough for any time at all before the bearings start to burn from dry running heat 
by hand packing i've had bearing last for years ver weeks,


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## WrenchIt (Dec 6, 2020)

I was going to measure the shaft and post pictures, but when I looked at the shaft with a Sherlock Holmes type magnifying glass, it looked like the area where the bearing sits has been abraded. The bump I mentioned is toward the forward end of the bearing - roughly half an inch from the base of the shaft. I considered doing the punch trick to raise metal, but had second thoughts. If the solid shaft wore down, half a dozen (or 8 or 10) dimples will not provide the same bearing surface as solid metal. This machine has been incredible for me for over 20 years, and I'm not going to pinch pennies now putting it back into first class mechanical condition. Toss in my own dislike doing the same work twice because I tried to save a few bucks and the knowledge that machines don't break when they are not in use or not needed made the decision easy. I called my local Honda dealer and ordered a new driven pulley w/ the shaft. If this lasts another 20 years, it will probably live longer than I will.


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## WrenchIt (Dec 6, 2020)

cpchriste said:


> I'd suggest a retaining compound. Sounds like a little fretting wear.
> www.machinebuilding.net/why-use-a-retaining-compound


A LOT of fretting wear. See my post above (#14).


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## cpchriste (Jan 19, 2014)

WrenchIt said:


> A LOT of fretting wear. See my post above (#14).


For future reference for others interested: Loctite 660 rated to .5mm diametric clearance as well as -65 to 300 °F 
It's worked well for me in this application.


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## orangputeh (Nov 24, 2016)

WrenchIt said:


> I was going to measure the shaft and post pictures, but when I looked at the shaft with a Sherlock Holmes type magnifying glass, it looked like the area where the bearing sits has been abraded. The bump I mentioned is toward the forward end of the bearing - roughly half an inch from the base of the shaft. I considered doing the punch trick to raise metal, but had second thoughts. If the solid shaft wore down, half a dozen (or 8 or 10) dimples will not provide the same bearing surface as solid metal. This machine has been incredible for me for over 20 years, and I'm not going to pinch pennies now putting it back into first class mechanical condition. Toss in my own dislike doing the same work twice because I tried to save a few bucks and the knowledge that machines don't break when they are not in use or not needed made the decision easy. I called my local Honda dealer and ordered a new driven pulley w/ the shaft. If this lasts another 20 years, it will probably live longer than I will.


I'd like to see a picture to see what you are talking about since I have not run into this problem. Have had problems with a wobbly pulley wheel but fortunately I have about 5-6 in my parts bins and just replace.

good call on replacing. I wish more of my clients were like you. some people want a ******* fix or a "cheap" fix and I usually say NO. Either do it right or take it someplace else.

Also a well maintained/repaired Honda can last OVER a lifetime. No exaggeration. My machines are 30-37-40 years old and still look and work as new.


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## 140278 (Aug 27, 2020)

cpchriste said:


> For future reference for others interested: Loctite 660 rated to .5mm diametric clearance as well as -65 to 300 °F
> It's worked well for me in this application.


it also makes for a very hard disassembly down the line, example the need of pullers and or a press something most home mechanics don't have access to .it's NOT a recommended repair in any shop manual , 
wrenchit is going the correct route, replace the parts as needed


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## cpchriste (Jan 19, 2014)

captchas said:


> it also makes for a very hard disassembly down the line, example the need of pullers and or a press something most home mechanics don't have access to .it's NOT a recommended repair in any shop manual ,
> wrenchit is going the correct route, replace the parts as needed


Heat or a cutting wheel would easily take care of bearing removal 20 years from now.

I'm not interested in trying to tell wrenchit which is the "correct route", I'm providing information.


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## crazzywolfie (Jun 2, 2014)

i am with cpchirste. if this is the first time in 20 years having this service it will likely be good for another 20+ especially if you grease the bearing good before installing them since it sounds like they don't get greased the best from the factory.


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## WrenchIt (Dec 6, 2020)

Note, Bearing I.D. is 0.7845 measured using my calipers.
Here goes. Pic #1: Shaft showing raised area.









Pic #2: Measuring diameter of area close to pulley, between raised ring and pulley.









Pic #3: Diameter of raised ring.









Pic #4: Diameter of shaft on impelller side of raised ring.









Pic #5: Width of area between ring and pulley. Note that the bearing wobbles when seated here. Calipers are not positioned accurately.









Pic #6: Width of raised ring.


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## orangputeh (Nov 24, 2016)

have never seen this. thanks for posting I thought you meant the area where the bearing seats was worn , thus causing the poor fit. that area is smoother than the rest of shaft. 

how does the inside of that end of impeller look like? showing wear? i thoroughly clean both end out and apply anti-seize grease.


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## WrenchIt (Dec 6, 2020)

Pictures guys. see my last post.


cpchriste said:


> Sounds like a little fretting wear.





Arcticnorth said:


> I changed the impeller bearing ...It was a perfectly tight fit, and there was no raised bump on the shaft.





orangputeh said:


> I'd like to see a picture to see what you are talking about





cpchriste said:


> For future reference for others interested: Loctite 660 rated to .5mm diametric clearance


On second thought, the depressed area where the bearing goes almost looks polished or worn by a spinning bearing. The old bearing, however, is not seized, it is just a bit noisy and fits snugly in the bearing retainer that bolts to the back of the blower housing. When I wrote my above post (#14) I must have been confusing the rough face of the pulley with the shaft.

Locktite might work since 0.5mm=0.01968 in. But, how do you center the bearing on the shaft?


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## WrenchIt (Dec 6, 2020)

orangputeh said:


> have never seen this. thanks for posting I thought you meant the area where the bearing seats was worn , thus causing the poor fit. that area is smoother than the rest of shaft.
> 
> how does the inside of that end of impeller look like? showing wear? i thoroughly clean both end out and apply anti-seize grease.


I don't remember it showing wear, but I will look again. Believe me, I use copious amounts of Aunt Seize on everything. Fingers, clothes, and a little dab on the metal. Seriously, I gobbed the stuff on the ends of the augers roughly 6 years ago when I found a newspaper in the deep snow and yanked everything apart checking for damage. The bearings were fine then, and they slipped off easily this time.


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## crazzywolfie (Jun 2, 2014)

the bearing could have possibly stuck and eventually worked itself free again which is why it is so noisy but caused some wear to the shaft


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## toromike (Aug 20, 2018)

WrenchIt said:


> . . . Locktite might work since 0.5mm=0.01968 in. But, how do you center the bearing on the shaft?


 You could use some shim stock with the retaining compound (or with just anti-seize). Harbor Freight has a feeler gauge set for $5 that would provide a variety of thicknesses.


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## 140278 (Aug 27, 2020)

looks like the ring area is where the shaft had a small shoulder machined to the flange, for the bearing to seat , a 2 or 3 thousand press fit makes sense. 
looking at the wear it's been spinning for a long time to wear down those few thousands, that can happen when a bearing seizes spins on the inner surface 
fixing it's a new part or a costly plasma weld build up and machine shop returning to the size of the ring area . 

out of your thread more to state price .i just rebuilt a 66 mopar 4 speed the input shafts pilot bearing end was worn like your shaft , when down saving a hard to find item i had laid out $200.00 for plasma welding and machining a 2 inch long spot


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## WrenchIt (Dec 6, 2020)

captchas said:


> looks like the ring area is where the shaft had a small shoulder machined to the flange, for the bearing to seat , a 2 or 3 thousand press fit makes sense.
> looking at the wear it's been spinning for a long time to wear down those few thousands, that can happen when a bearing seizes spins on the inner surface
> fixing it's a new part or a costly plasma weld build up and machine shop returning to the size of the ring area .
> 
> out of your thread more to state price .i just rebuilt a 66 mopar 4 speed the input shafts pilot bearing end was worn like your shaft , when down saving a hard to find item i had laid out $200.00 for plasma welding and machining a 2 inch long spot


I don't know if the bearing was a press fit on the shaft when new. As I said, the bearing was not seized, it spins freely, it was dry, and if the bearing were spinning, I would expect heat discoloration. Regardless, the new shaft/pulley assembly costs me $62 plus tax and a 20 min trip to the dealer. I was not about to start looking for a machine shop for that price.


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## orangputeh (Nov 24, 2016)

WrenchIt said:


> I don't know if the bearing was a press fit on the shaft when new. As I said, the bearing was not seized, it spins freely, it was dry, and if the bearing were spinning, I would expect heat discoloration. Regardless, the new shaft/pulley assembly costs me $62 plus tax and a 20 min trip to the dealer. I was not about to start looking for a machine shop for that price.


it is not a press fit. when you replace the bearing be sure to use some loctite on the 3 little bolts for the bearing holder. 

plus you already know to use anti seize on the pulley shaft.

I have run across many seized bearings on these shafts. either have to cut off or use a gear puller if pentrating oil doesnt work.


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## WrenchIt (Dec 6, 2020)

orangputeh said:


> I have run across many seized bearings on these shafts. either have to cut off or use a gear puller if pentrating oil doesnt work.


At first I tried using a two piece gear puller - the two type that has a circular flat area that slides in behind the bearing. Two bolts go to a slotted piece of steel with the threaded rod in the center that bears on the bearing's shaft. The problem I ran into was the bearing holder was in the way. I assume there are larger pullers of the type I am talking about that would reach in behind the bearing holder.

What do you use to pull these bearings? There is/was barely enough room behind the holder to slip a solid piece of steel in there and use a press.

Edit: How do you cut the bearing off without damaging the bearing retainer? I'd guess both are sacrificed if the bearing won't slide off the shaft.


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## WrenchIt (Dec 6, 2020)

orangputeh said:


> should not be a loose fit. impeller bearing for impeller should be 6004UU and the number should be on rubber seals.


The bearing I got is an NMD 6004 2RS. The 2RS means two seals, I could not find a meaning for UU but i think I read it meant rubber seals. The RS are two contact seals. See my other post, #13 in this thread. The bearing does not wiggle, but it is not tight on the shaft. If you have not heard of NMD, I'll pop for an expensive Honda OEM bearing, else I can use Locktite 641 - a bearing locker. I can always heat the shaft/bearing to break the glue bond.

Edit: I just measured the bore of both bearings - new and old. The old one measures 19.97mm and the new one 19.98mm. I can probably fiddle around and get both to measure the same, either .97 or .98 so as far as I am concerned, both are the same. The ID of the old one was simply dirty, no real wear visible like on the shaft.


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## ST1300 (Feb 17, 2017)

If you want to see what a pulley shaft looks like with the raised area take a look at page 2 of the parts for sale. Pictures are a 928 pulley with shaft with very little wear (almost looks new). I posted this 9 months ago but still have it. Send an e-mail or call if you are interested.


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## Clipperskipper (Dec 24, 2015)

I went down this path on my HS928TAS several years ago, purchased a nice Japan bearing on Amazon for $5.99, 
6004-2RS double sided sealed ball bearing 20MM X 42 MM X 12MM. 20MM is the shaft diameter, or .787"for a snug fit.


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## cpchriste (Jan 19, 2014)

I'm resurrecting this old thread because I lost track of it back when. I want to address this point


WrenchIt said:


> Locktite might work since 0.5mm=0.01968 in. But, how do you center the bearing on the shaft?


You can center the race on the shaft by dimpling the shaft in several spots. This will create a more uniform and thinner layer of loctite on the shaft.
However the centering isn't necessary to do for imbalance. I calculate the centrifugal force created by off-centering the bearing by .02" to be 5 pounds.


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## WrenchIt (Dec 6, 2020)

cpchriste said:


> I'm resurrecting this old thread because I lost track of it back when. I want to address this point
> You can center the race on the shaft by dimpling the shaft in several spots. This will create a more uniform and thinner layer of loctite on the shaft.
> However the centering isn't necessary to do for imbalance. I calculate the centrifugal force created by off-centering the bearing by .02" to be 5 pounds.


In the end I didn't bother. My new impeller pulley's shaft was either made improperly by Honda or not, but I applied the Loctite and assembled the blower/bucket/augers. The bottle said it sets up in 24 hours, I was finished w/ alignment and the major assembly within 1 1/2 hours. The machine works fine, tho I admit I did experience a bit of a problem after setting the belt guide per the Honda Service Manual. Said guide rubbed on the outside of the belt and melted the outside or top surface. So much for using aftermarket belts. I've ordered new Honda belts and I'll change them out probably after the snow season ends. The melting is only on the surface, and I probably don't need to do this, but the original belts lasted 20 years. I doubt I have more than 10 more years of manual snowblowing.


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