Stihl MS 261 C-M

gmacmopar

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White spots? Sounds like your old mix had water in it and you finally got it out of your system.
Well I thought either to lean or water. But still there's the problem of not starting when it is hot. I'm going to dump the fuel and put new fuel in. My wife's son-in law has had this saw for over a year and he said it wasn't running very good???? Imagine that!
 

bertsmobile1

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Just about every new engine runs way way way too lean
Thus now days not uncommon to find engines that will not start unless the carb is choked, even when hot .
So next time try a couple of pulls with the choke on.
After 10 pulls that did not fire your plug should be wet.
Not soaking wet but wet just the same ,
 

gmacmopar

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Ok I will try that. Should I change the fuel filter while I'm messing with this?
 

gmacmopar

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Ok I got it started and let it run with the brake on for about 30 seconds. Then took the brake off and ran it wide open for about 90 seconds. Shut the saw off and tried to restart with the choke on after 10 to 15 pulls no start. Took the plug out and dry as a bone with the electrode being somewhat white? Ok maybe carb issues? I put a new fuel filter on the saw with fresh well mixed fuel so I know that is good. I will wait for your replys.

Thanks
 

bertsmobile1

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Sounds way too lean
Do not try & start the saw with the brake on
I am yet to find one that will happily start & warm up with the brake on as it puts a massive load on the engine
Imagine trying to start your car in gear with your foot on the brake
I am not familiar with this saw and can find bugger all in the way of tune up info
Does it have a butterfly carb ( high & low speed jets + throttle stop ) or a rotary valve carb ( just a throttle stop )
 

gmacmopar

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There is no adj on the carb it is all controlled by the solenoid and Stihl has a special meter to adj things that I do not have.
 

StarTech

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There is a procedure to do it without the Stihl test equipment.

This is extracted from the MS261 C-M service manual. Note: 30 cm is approx 11.8 inches.

1662809009188.png
 

Hammermechanicman

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Should change the name to "All Star Tech" with all the info he has and provides.
 

gmacmopar

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I can get the saw to max speed when starting it cold with the choke the problem is it will not start after it is warmed up or has ran a while.
 
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