550xp mkii running on

[stewmo]

My saw started running on today. Can’t see any reason why and nothing to fiddle with. Chain correct tension. Air filter clean. Newish plug.

 

Other symptoms, sounds a bit throaty on tick over maybe. Still good power when cutting but occasionally cut out once out of the wood.

 

Recently the needle bearing broke and was replaced.

 

Stopped using fairly quickly for obvious reasons.

Not sure what else to say.

 

Any thoughts??

 

Thanks in advance

[bettio]

I had similar issues with my mk2 550xp and ended up being the tank vent was faulty. Try taking the fuel cap off whilst running on to see if it settles.

[spudulike]

Running on? Are the revs elevated or are we saying the chain is spinning on low revs. Check the clutch springs, perhaps one has gone and check the needle bearing as well seeing as it failed before.

[stewmo]

Running on? Are the revs elevated or are we saying the chain is spinning on low revs. Check the clutch springs, perhaps one has gone and check the needle bearing as well seeing as it failed before.

Chain is spinning on low revs.

Needle bearing only changed it a month ago.

Will check springs but from memory they are so big how could they break?! Not like a 200t clutch spring

Thanks

[stewmo]

I had similar issues with my mk2 550xp and ended up being the tank vent was faulty. Try taking the fuel cap off whilst running on to see if it settles.

I’ll try this out thanks

[spudulike]

If the chain is spinning on at low revs then it is likely to be clutch springs, knackered needle bearing, something binding between the clutch drum and clutch or the clutch having spun off and then tightened without being meshed with the oiler pinion correctly.

Springs are spring steel - they can all crack including the forking great springs on your car!!

[stewmo]

If the chain is spinning on at low revs then it is likely to be clutch springs, knackered needle bearing, something binding between the clutch drum and clutch or the clutch having spun off and then tightened without being meshed with the oiler pinion correctly.
Springs are spring steel - they can all crack including the forking great springs on your car!![emoji6]

Ok well I’ve got my maintenance list from spud once again

[spudulike]

That is how it is....you asked, I gave and now you do

[Darkslider]

Even if clutch springs look ok externally they can wear through the hooks and the spider so there's no tension on them anymore, not always obvious till you take the clutch off and it's a bit looser/more wobbly than you remember. 

 

I'd bet Spud is on the money with something jamming or binding the shaft or clutch to the drum though that's the problem 9 times out of ten for me. Cheap needle bearings off eBay seem to cause it more often in my experience, doesn't take much of a bind in a cheap bearing to turn a well oiled chain with no resistance 👍

[stewmo]

So got the clutch off and needle bearing gone again.
Bought from L&S engineers so shouldn’t be eBay cheap surely?
And yes it’s jammed the clutch housing (if that’s what it’s called) onto the shaft.

So tips on how to get it off and...

What’s going to be underlying cause of two needle bearings going one after the other?