056 not lighting......Is it the carb?

[sawhawg]

My Stihl 056 quit on me today...symptoms acted like the high speed jet was plugged,it would idle ok but bog when I tried to rev it up.Originally thought that it might be ice/water in gas,'cause it was running fine when I shut it off for about 20 minutes,picked it up to make a cut,and couldn't get it to rev.Further exploration led to discovery of a severed ignition ground wire...which I thought might be arcing and causing intermittent cut-out.Spliced that,changed the gas,got it running...seemed to "come into it",got a good crisp response with no bog from low idle to high rev(didn't sit there wide open,but adjusted jetting to the sweet spot from low r's to rev)...it was a little lean on idle,so I tried to lower her idle speed a bit...and she quit again.Set low idle back to factory setting (1 1/2 turns out),pulled and pulled and could not get her to light.Nice blue fat spark at plug....good compression(120lbs)...but seems like plug is staying dry.Put a little gas in cylinder,she'll fire and pop,but won't take off.When this saw is right,its basically effortless to light her...couple half pulls on the rope choked cold,fires once,open choke and shes good to go.If I'm having to pull and pull until beads of sweat on the forehead....efinitely something amiss.So we've got good compression...good spark...but a dry cylinder.I'm thinking...gotta be the carb?Never dealt with a carb failure,but I think shes original....and has seen her share of ethanol....any feedback on symptoms of carb failure appreciated.Are all the carbs on the 056 Tillostons?...Thanks....*******

 

[Dan_IN_MN]

Does this saw use an impulse line? Check it.

 

[DanS]

this sounds like the ignition is buggered. known issue with these saws. if you have the bosch (electronic) ignition, then you can get a replacement part from german ebay for 90 euros. these are proven to work. if you have an early SEM, you're stuffed. if you have a later SEM, it's the same part as is on the 08/08S/ts350.