550xp mkii needle bearing conundrum

[stewmo]

My 550xp seems to be chewing through needle bearings. 

Just had one go today that is only 5 weeks old and some days or even weeks the saw doesn't even get used. The one before that lasted 3 months. 

When I took the last one off it was almost melted on to the inside of the clutch drum. And today the same sypmtoms......chain spinning on idle and when chain brake applied the saw stalls, presumably because the crank can't turn. So I am assuming when I take this one off it will be same.

Once is an oddity but twice....makes me want to know what is going on? Is there a deeper issue here that needs correcting as well? 

Thoughts welcome!!

[openspaceman]

Weak clutch springs overheating the drum on idle??

[adw]

Insufficient greasing, leaving the saw idling for too long, when the saw is left idling the grease is soon lost, the crank journal is hot so eventually you have metal to metal with no lubrication, the bearing over heats and the cage breaks up.

[Dan Maynard]

Is it dragging on the brake band? Maybe just insufficient cleaning and chip build up? Must be a cause, something is different about the saw or the way you use it, else it would behave the same as all the other people not having this problem.

[stewmo]

38 minutes ago, adw said:

Insufficient greasing, leaving the saw idling for too long, when the saw is left idling the grease is soon lost, the crank journal is hot so eventually you have metal to metal with no lubrication, the bearing over heats and the cage breaks up.

I get what you are saying.
But why now? The saw is years old and never had a problem before. 

[stewmo]

45 minutes ago, openspaceman said:

Weak clutch springs overheating the drum on idle??

Clutch is fairly new so I think unlikely but you never know 

[Trailoftears]

As far as I understand it,the spindle bearing cage only spins at idle when v.little heat is generated-is that item in the piccy a metal orplastic cage out of interest?It could be either the drum has interior eccentric internal wear,or looking on the black side- the crankshaft isnt running true?

[stewmo]

7 minutes ago, Dan Maynard said:

Is it dragging on the brake band? Maybe just insufficient cleaning and chip build up? Must be a cause, something is different about the saw or the way you use it, else it would behave the same as all the other people not having this problem.

Exactly. Something is causing it. Nothing I am doing is any different from before or with any of my other saws. Brake band is an idea….

Edited November 7, 2022 by stewmo
Added text

[Dan Maynard]

2 minutes ago, stewmo said:

Exactly. Something is causing it. Nothing I am doing is any different. Brake band is an idea….

And you say the saw is years old so something has definitely changed. Have you recently changed the chain, bar, sprocket or clutch drum?

[Stubby]

Sounds very similar to the early Stihl 261 syndrome . Oval crank or something like that I think it was .