Profanity & nylon caged bearings...

[tickbitintn]

Will the updated bearings fit on the older model cranks/cases or are the cranks/cases different also?


Sent from my XT1254 using Tapatalk

 

[Mattyo]

Walt? @afleetcommand

 

[Dirtmagnet]

Is it possible to have custom ceramic ball installed then the nylon cage swapped out to stainless?

That is likely way too expensive, but interesting idea! Best would be to just use a full steel bearing, but of course it would have to be custom made as well. Too bad because people really like these saws.

 

[Fullkip]

I had an idea about the plastic caged bearing so I played around with it.. Pop the seal out of a 562 bearing and then snap the nylon bearing cage out. Take a 6202 and carefully remove the metal bearing cage. I checked the bearings are the same dia... Install in the 562 bearing. I did it on the clutch side. Snap seal back into place.The 6202 was an SKF....
All I need is a source for SKF cages and the 562 bearing seal. Not sure if the seal can be reinstalled without an air leak. Might need to make a cage crimp tool...
Might be just dreaming...

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[Mattyo]

I'd be impressed if ya did it

 

[Onan18]

I had an idea about the plastic caged bearing so I played around with it.. Pop the seal out of a 562 bearing and then snap the nylon bearing cage out. Take a 6202 and carefully remove the metal bearing cage. I checked the bearings are the same dia... Install in the 562 bearing. I did it on the clutch side. Snap seal back into place.The 6202 was an SKF....
All I need is a source for SKF cages and the 562 bearing seal. Not sure if the seal can be reinstalled without an air leak. Might need to make a cage crimp tool...
Might be just dreaming...

Fullskip

The seals are available as a service part from Husqvarna

 

[Fullkip]

I did get the 6202 metal cage re crimped over to the PTO side SKF BB1 3023 EC . It took a little bit of fiddling around... The 6202 cage is a two piece one , the little tabs on one side fold over on the other to hold it together. If you can get the seals that snap into the 3023 I would be all over doing this mod. Back to my dealer I go...Anyone know peps at SKF to source bearing cages? I have some 6202s that are going to loose there cages.. lol ... I have several 5 and 6 screw cases that are going to get the mod only to the pto side bearing... Once I finish the 3 builds I'm in the middle of...
So why did they go to nylon cages? Was it just to save a buck!!! As far as I can tell other then the cages and the width the 3023 is a 6202 witch are a well proven bearing.

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[Tor R]

So why did they go to nylon cages? Was it just to save a buck!!! As far as I can tell other then the cages and the width the 3023 is a 6202 witch are a well proven bearing

Husky started with non industrial bearing back in 1978 with their 40, a concept they continued with on 44/444/133/234/238/242 and so on. The first of them had some sort plastic, later they made them with metal cage.
New style PTO bearing came with 351/346, a bearing they continued with on 550/560/562.

I dont know why they still stick with nylon materiale, but its easy to understand why they more and more left the traditional 6202 bearing.

 

[Spike60]

I dont know why they still stick with nylon materiale, but its easy to understand why they more and more left the traditional 6202 bearing.

Let me try and share a little info on this. It has been a continuing source of anguish for my best buddy, so I thought I'd reach out to a contact I have in Sweden and get some explanation. Obviously there had to be a reason for them to prefer the plastic cage bearings. I fully understand that we all draw conclusions from what we see with our own eyes. Some of us see more than others, and the larger the data sample, the more accurate those conclusions are likely to be.

Simple version is that in both lab and field tests the nylon cages have proven to be superior. The nylon has some elasticity to it that is not present in steel cages. A cold start, especially in winter when everything is real tight is when the cages see the most stress. And in general running on acceleration and full load RPM. After switching from steel to nylon, failures actually went way down. I'm sure many guys will stick to what they think, but that's the other side of the story from the other side of the ocean by someone who really knows his stuff.

 

[5000+]

Stihl has used nylon caged bearings that held up ok. I thought on elux blamed some failures on assembly methods at the factory.

 

[Spike60]

Stihl has used nylon caged bearings that held up ok. I thought on elux blamed some failures on assembly methods at the factory.

That did occur on a limited run of 372/2172 saws. Some of the bearings were not installed correctly. I think it was an early 2011 time frame? Not like it was every saw that came off the line, and most didn't fail. But enough did that yes, it was a legit problem. Any saw from that era that is still going certainly came off the line in good shape, so no need to worry if you have one.

 

[Mattyo]

Can someone please define "not installed correctly "?????????

 

[Mattyo]

Ie...someone used a sledgehammer??

 

[Fullkip]

I heard something to do with cracked cages when being installed .... the failures I have had were heat caused at least as far as I could tell. 300 plus hour run times or more. Maybe they weren't putting pressure only on the inner race...

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[Fullkip]

I heard something to do with cracked cages when being installed .... the failures I have had were heat caused at least as far as I could tell. 300 plus hour run times or more. Maybe they weren't putting pressure only on the inner race...

FullSkip

I heard something to do with cracked cages when being installed .... the failures I have had were heat caused at least as far as I could tell. 300 plus hour run times or more. Maybe they weren't putting pressure only on the inner race...

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[Fullkip]

Here is an example from one of my personal saws...

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[Tor R]

Can someone please define "not installed correctly "?????????

I've seen it once on 550 xpg year 2015.
Probleby a tad off angle when they press the bearing into the case, final result where magnesium shavings between the seal socket and bearing, ie bearing never got the correct depht.

 

[Fullkip]

Sorry about the screwed up post... I tried to post a pic of a smoked bearing cage...
It worked this time...

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[Mattyo]

I've seen it once on 550 xpg year 2015.
Probleby a tad off angle when they press the bearing into the case, final result where magnesium shavings between the seal socket and bearing, ie bearing never got the correct depht.

Tor, can you post a pic of the mag shavings in the pocket?

I just have a hard time imagining this. So there is a 100 ton press somewhere thats jamming bearings into pockets off angle? either A, they are using the wrong tool for the job in the first place, or B, its an excuse. The cage itself isn't under load. Even if you press the bearings in by the inner race the pressure is laterally between the balls and the races... not on the cage. the cage doesn't hold pressure... just spaces the balls correctly. So long story short. I ain't buying it.

Even if the bearing was THAT much off angle, the crank has nearly zero give. So as soon as the crank goes in, the bearing would straighten at least somewhat, or have a massive amount of drag on it to begin with. but its STILL not putting pressure on the cage. drag = heat .. heat destroys nylon. so...that I can understand. but an off center bearing... ??

there IS a reasonable answer available... I just haven't heard it.

 

[Tor R]

Matt, I didnt take picture, but there was no doubt of what had happen, magnesium pieces in bearing pocket was a clear answer for me.

When you press a flywheel bearing in, you dismantle it again, you find pieces from the mag case in the bottom of your bearing pocket, your bearing mounting was wrong.
1) when there is mag pieces there, your bearing did not got the correct depht, it wasnt set deep enought because the mag pieces you shaved of prevented the bearing to bottom in the case.
2) your crank may not be 100% free due the reason stated over.

I belive it happen because they had not centered the bearing before they started to press, it doesnt take much off the center in the start before a bit of the case get shaved a tad, and unfortantly, in most cases like that 550 it was enough.

PS, to those who plan to start with cold pressing, you will never see if you shaved to case a tad when you pressed the bearing in, seal pocket hide your mistake, use heat is 100% safe!