Profanity & nylon caged bearings...

[Mattyo]

I can understand if debris is in the pocket, and then the bearing is ...canted. if there is ANY cant at all to the bearing, there will be drag on the bearing. I get that. during a production process you might not catch that in quality control...

seems like a diyer would catch it if there is so much drag as to ruin a bearing. ...even if its cold pressed.

also. ...those bearings don't have sharp edges on them. the edge on the outer bearing race is round. assuming the magnesium chassis is also smooth enough, what would create the shavings?

 

[wcorey]

...also. ...those bearings don't have sharp edges on them. the edge on the outer bearing race is round. assuming the magnesium chassis is also smooth enough, what would create the shavings?

Caused by 'galling', sort of pushes/smears the softer metal out ahead of the harder stuff, like a wave.
In this case would likely look similar to fingernail clippings...

 

[Mattyo]

like an aluminum piston in a plated bore... with no lube

 

[Tor R]

Caused by 'galling', sort of pushes/smears the softer metal out ahead of the harder stuff, like a wave.
In this case would likely look similar to fingernail clippings...

yup Bill, tiny chips but long they was.
My first thought was wrong mounting, but the result would be the same if the bearing pockets was a bit outside specification.

 

[Mattyo]

any chance those chips could be leftovers from machining the bearing pocket in the first place?

 

[Tor R]

any chance those chips could be leftovers from machining the bearing pocket in the first place?

well, I've never done machine work on magnesium Matt, but I would be surprised if they pressed new bearings in a case with leftovers.
Its different for us who repair a chainsaw as hobby, we have all the time we need, I've worked on production factory before, speed is everything.

 

[Lightning Performance]

Ijust got here., oh I'm here now. I have and 024 here with nylon pto and steel wheel side.

Just about all stihls I get in to fix gets a complete tear down.95% of the time the cages are cracked.the other 5% are stickin to the roof of the combustion chamber and exhaust port.peanut butter must be the main ingredient for the cage material.lol

Are the jugs and pistons still good?

We sure have got some great members.

Excellent thread gents.

Agreed

like an aluminum piston in a plated bore... with no lube

Ah,no that would be a "smear smearing" you pick. Like painting hot chrome with aluminum, comprenday?

This saw seems tight. Just the opposite of what TreeMonkey showed.

 

[Lightning Performance]

The cage looks good and so does the plastic,no discoloration. This is Low low hrs saw. It has a fresh meteor top. It turns smoooooth but like it has cold gear oil in the bearings, wtf. Should I wash heat and repeat? The case gasket has some white sealer I have never seen on a production saw before.
Have you?

 

[Mattyo]

well, I've never done machine work on magnesium Matt, but I would be surprised if they pressed new bearings in a case with leftovers.
Its different for us who repair a chainsaw as hobby, we have all the time we need, I've worked on production factory before, speed is everything.

ie, they have a 100 ton press slamming these things home. lol

I totally get the speed thing. but if they had an improper installation of bearings, that implies that they found the proper way... if so...how? realignment of their press so the bearings go in straight?

on the production line it would seem to me easier to have warm chassis travel past someone picking bearings out of liquid nitrogen and dropping them into place. THAT seems like it would be fast and proper ... on a production line anyway

 

[Jughead]

Ijust got here., oh I'm here now. I have and 024 here with nylon pto and steel wheel side.


Are the jugs and pistons still good?

Agreed
Ah,no that would be a "smear smearing" you pick. Like painting hot chrome with aluminum, comprenday?

This saw seems tight. Just the opposite of what TreeMonkey showed.

yes most of the time they are good.only saws that have let yhe bb's loose are the newer 291 311 series.

 

[Lightning Performance]

No nothing, really... Just assumed running it by some others would bring a few fresh ideas.

Has anyone seen an older 024 factory built saw with white sealer looks like 5400 marine white on the case gasket?

PTO side is plastic cage and the flywheel side is steel cage. Everything looks beautiful.

 

[Spike60]

Matt you gotta chill out. The machine was off, the bearings were off, it was a limited run 6 years ago, they fixed it., it's over.

Have a beer and relax Buddy.

 

[Mattyo]

Wine tonight.....

So....what you are telling me is that the machine was out of alignment...which is fine. I have no problem with the words that come out of your mouth Bob...you know your sssshhh. But. When I hear "incorrect installation" I gotta wonder what the actual definition of that is. I really don't like intentionally vague excuses from major manufacturers.

For myself. ..I'm avoiding those bearings entirely. I know how wonderful the 562 555 and 550 are supposed to be....but for me I'll stick to saws that I don't have to use proprietary bearings for. My 385 is going out the door asap in favor of 394s or 372s.