The Forestry Forum

General Forestry => Chainsaws => Topic started by: ejkelehan on January 31, 2011, 04:59:43 PM

Title: Stihl 025 won't idle
Post by: ejkelehan on January 31, 2011, 04:59:43 PM
          Howdy all, new to the forum here, I mainly cut firewood and my Dad builds custom cabinets, so he's been looking for a mill for a while, anyways, I just rebuilt the Carb on my Stihl 025 due to a rough idle/ not idling, and occasional hot start issues, now that it is rebuilt, the saw will only run at full throttle, i have tried all sorts of Carb adjustments with both the idle and low adjustments, but it will only run at WOT, my next thought is either the ignition coil, or maybe the fuel line is only providing enough vacuum to suck fuel into the Carb at WOT...any ideas to the root of the problem? Besides convincing my dad to get a bigger saw, I've been trying that for the past 6 months (I'm only 16).
Title: Re: Stihl 025 won't idle
Post by: lumberjack48 on January 31, 2011, 06:23:10 PM
Sounds like real bad air leak, check the boot between the carb and the head, it might  be lose 
Title: Re: Stihl 025 won't idle
Post by: ejkelehan on February 01, 2011, 09:13:06 AM
Ok. Ill check that when I get home. Thanks
Title: Re: Stihl 025 won't idle
Post by: Saw Dr. on February 01, 2011, 03:17:18 PM
I have seen a BUNCH of 1123 series saws with bad crank seals.  Check the fuel line first, and if any cracks are present replace it.  Check the little metal plate behind the carburetor.  It is possible to have the gasket positioned so as to block the impulse passage.  Also check the impulse line for condition and make sure it is attached on both ends.  I have seen it get pulled off at the top by YANKING the saw out of a pinch.  Generally, one or more of the A/V mounts will be mis-aligned if this is the case.  The compression should be 130+ for a reliable idle on this saw.  How does the piston look on the exhaust side.  If the carb is clean, assembled correctly, and the rest checks out then plan on replacing the crank seals.
Title: Re: Stihl 025 won't idle
Post by: ejkelehan on February 01, 2011, 08:04:46 PM
Thanks for the information. Ill give it a shot tomorrow afternoon. What exactly is the impulse line? I'm not too knowledged in 2 strokes. Is it similar to a vac. Line on a car?
Title: Re: Stihl 025 won't idle
Post by: sawguy21 on February 02, 2011, 12:17:26 AM
The impulse line connects the fuel pump in the carb and the crankcase. It allows the crankcase pulsations to operate the pump. A leak here will mean the pump won't work and air will get in the crankcase when it is not supposed to causing an over lean condition.
Title: Re: Stihl 025 won't idle
Post by: ejkelehan on February 02, 2011, 01:05:55 PM
sounds like that could be my problem, since it is running to lean to run at anything but full throttle, Ill have to look into that...any chance you have a service manual for 1123 model saws?