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MS260 carb problem


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............or more likely user problem :001_huh: Chain runs while at idle. It's correctlty tensioned. Like an idiot I started messing around with the L screw only, then realised the error of my ways, ground my teeth a bit and thought I'd bung it back to the specified setting which is enscribed on the side of the air filter cover. So I gently turned it anticlockwise without paying attention to how far it had gone around, expecting to find the limit of turning so I could then turn it back to what it said to. There was no end to the turning. There appears to be no bottom limit. Turning it does alter the running of the saw but there is no way to quantify how many turns from zero. I got it running again as it was before but now I'm not up for using it until I'm sure the settings are correct!

 

I have not touched H or LA. They are as they were. When I start the saw now it seems to run fine apart from the idle run-on, when I increase throttle it progresses smoothly with no struggling. It doesn't cut out while idling.

 

My question is, now I've made a fool of myself, what's the likelihood of causing damage to the saw through having buggered about with 'L'? It doesn't feel as though it's wrong, but now I can't reset it to factory settings, I'm dubious about using it. I could take it to local dealer at £60+vat+parts which I'd rather not do, but will if I have to. Like i said, H and LA remain untouched.

 

There are some things on this earth that I wasn't meant to touch, one of those things was carb settings. Other things include cooking fish, maths and boxing.

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Ok. So lets bring in the other thread.

 

Run on may be caused by worn clutch or drum. This would have sounded like the cause, or with the over oiling maybe oil has made it onto the clutch causing it to slip.

 

Could be in connection with the over oiling.

 

Turning the L screw in too far will cause the saw to run lean, this could end up in a lean sieze, but by the sounds of it the L scre isn't doing anything. First thing I would do is clean the carb out, remove both screws and give the holes a blast with cleaner.

 

The saw would be worth checking with a tach. Just to make sure its idling at the correct rev.

 

When adjusting the screw from factory, turning in will cause the saw to over rev, turning out will cause the saw to run rich.

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............or more likely user problem :001_huh: Chain runs while at idle. It's correctlty tensioned. Like an idiot I started messing around with the L screw only, then realised the error of my ways, ground my teeth a bit and thought I'd bung it back to the specified setting which is enscribed on the side of the air filter cover. So I gently turned it anticlockwise without paying attention to how far it had gone around, expecting to find the limit of turning so I could then turn it back to what it said to. There was no end to the turning. There appears to be no bottom limit. Turning it does alter the running of the saw but there is no way to quantify how many turns from zero. I got it running again as it was before but now I'm not up for using it until I'm sure the settings are correct!

 

I have not touched H or LA. They are as they were. When I start the saw now it seems to run fine apart from the idle run-on, when I increase throttle it progresses smoothly with no struggling. It doesn't cut out while idling.

 

My question is, now I've made a fool of myself, what's the likelihood of causing damage to the saw through having buggered about with 'L'? It doesn't feel as though it's wrong, but now I can't reset it to factory settings, I'm dubious about using it. I could take it to local dealer at £60+vat+parts which I'd rather not do, but will if I have to. Like i said, H and LA remain untouched.

 

There are some things on this earth that I wasn't meant to touch, one of those things was carb settings. Other things include cooking fish, maths and boxing.

 

Firstly, chill, life is too short, so what the oiler is pissing out more oil than the average oil well:lol:

 

The L screw is the screw closest to the cylinder. It is unlikely you will do damage with what you have done as the later carbs H&L screws work independently to each other so the L screw adjustment won't lean the saw out. This wasn't the case on the older 026s that can be a pig.

 

You have to be careful with the indications on the air box as if the red limiters have been removed from the carb, they will be wrong - I have seen saws lean seized due to this.

 

Just shine a light down the hole where you adjusted it and see if there is a small black screw down there or a red plastic plug. The fact you were able to keep turning makes me think they have been removed.

 

If the limiters have been removed, both screws should be one turn out from fully in - this gives the basic setting.

 

If the chain is spinning all the time - is the idle a bit high? if it is then the LA screw will bring it down but if it is idling normally then it may be the clutch springs need replacement or just crap in and around the clutch drum or twine wrapped round the end of the clutch....or a knackered needle bearing.

 

Does the saw run with the chainbreak on?

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That properly makes sense! When running, the oil covers everything! I've just noticed that I was turning the screw the wrong way anyway (:001_huh:) and i was going to delete this pure idiotic fact. I've now found zero and changed L to it's intended single turn. This would explain the run-on and now shows not to play with the LA/Carb until the oiler is sorted.

 

Thank you!

 

I feel like a total plum now for turning the wrong way :biggrin: I make mistakes so other people don't have to.

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ps: the chain doesn't run when brake on. The clutch looks in fine condition and there is no fishing line or similar beneath this (I've had this before and it tends to be the first thing to look for when other chains have run on, and in all cases apart from today, it was fishing line).

 

Again, thanks for the replies!

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ps: the chain doesn't run when brake on. The clutch looks in fine condition and there is no fishing line or similar beneath this (I've had this before and it tends to be the first thing to look for when other chains have run on, and in all cases apart from today, it was fishing line).

 

Again, thanks for the replies!

 

Sounds like the clutch springs may be a bit worn, common problem on most saws at sometime in their life.

 

Will cost you around £5 for the springs, you will need to remove the clutch to make changing them easier - it is a left hand thread so turn the clutch clockwise to remove it!

 

You will need to lock the piston in place using a piston stop - use the double ended Stihl one as it wont damage the piston like the steel screw in ones will. Rope down the plug hole also works but the Stihl stop is without doubt a decent too when used correctly.

 

The clutch can be removed with a wrench and socket - you may need a long reach one.

 

Just remove the old ones with long nose pliers or screw driver and put the new ones on by hooking one end on the clutch shoe and use a piece of string round the hook on the other end to give good purchase when stretching it to fit.

 

That should sort it:thumbup:

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