Chainsaw revving

Anonymous-0 · May 26, 2013

When my stihl 036 gets warm it revs and the chain spins like mad when 'idling'? But it's not idling its partly running. Any ideas? Is it my gas mixture? I'm using 50:1.

Andy C · May 26, 2013

Cracked fuel line? Air getting in carb leaning it out....
Andy

Zachary Hoyt · May 26, 2013

Check your carb adjustment screws. I do not know the settings for that saw, but you should be able to adjust one screw to control the idle speed.
Zach

scott mcintosh · May 26, 2013

Besides fuel line also check pulse hose they both go bad,another possibility is crank shaft seal.Scott

Jiles · May 26, 2013

(quoted from post at 02:43:15 05/27/13) When my stihl 036 gets warm it revs and the chain spins like mad when 'idling'? But it's not idling its partly running. Any ideas? Is it my gas mixture? I'm using 50:1.

Check to make sure linkage is not holding carb slightly open. If not, you probably have an air leak. I would check the carb mounting boot first then I would suspect crank seals.
Is this a new for you saw? If not, I don't think you have a carb issue but I would adjust each screw out 1--1 1/4 turns.
An air leak is bad news for a 2 cycle engine. The motor will seize if not corrected!
With all chainsaws the "H" carb screw should be set to "4-stroke"-- when run at wide open throttle--but not in a heavy cut.
This can be done by holding the saw wide open and adjust for highest RPM--then turn screw out 1/8 turn until it seems to be choking up (four stroking). I have seen lots of mechanics overdo the revving but I only hold the throttle wide open for 3 to 4 seconds with each test
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JerryS · May 27, 2013

Whatever the cause, get it fixed. A non-stop chain saw chain can be bad for your health. Otherwise, you might stupidly raise your knee into it when stepping over a brush top or something. Not that that ever happened to me.

Billy NY · May 27, 2013

Might be a good idea for a small engine tachometer, and get some spec's on the carb settings, lean it out, over rev, definitely not good. My MS390 seems to take longer for the chain to stop, always once the engine is hot.

Texasmark1 · May 27, 2013

My chainsaws fuel ate up the fuel lines, especially the clear ones with the yellow tint. Other thing is carboning up. I use Sea Foam to decarbonize my old saw and weed eater. I put a can (16 oz) to my 50:1 oil mix gas can which is a gallon. Run it awhile and let it rest. Do it a few times and mine ran like a top. If you are doing any good it will smoke like crazy till it dissolves and burns out all the carbon. Just continue to use the fuel till all gone. Refill with mix as you normally do. Putting in a new spark plug when finished tops it off.

Mark

Anonymous-0 · May 28, 2013

Typical of an air leak.

Chainsaw revving

Anonymous-0

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Andy C

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Zachary Hoyt

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scott mcintosh

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Jiles

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JerryS

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Billy NY

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Anonymous-0

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