mirecc

RESOLUTION: Bought and changed both crank seals(pressed on with rolled plastic foil in middle to prevent spring from catching on inner race) and gapped magneto(coil). Primed the bubble, choke on and it puffed right away. One more pull and it was fast idling. Thanks for help guys.

UPDATE: after I have aqired some internet wisdom, I have checked "impulse channel" and cleaned whole carb. No visible scoring on piston skirt/ cylinder walls. All my older saws had actual impulse line so i thought that maybe membrane is somehow actuated by electronics (stupid me) on this one. So most likely it is not holding vacuum. Need to make some blanks and test it tomorrow. Probably I will buy crank seals right away when I'll be in town and change them anyway. Hope that will sort this.

Haven't pressure tested the crankcase but i am positive that no fuel is coming through carb into cylinder. Maybe it is worth to disassemble it and try to blow nozzle and passageways, check strainer etc. Maybe there's just something clogged up somewhere? It's earlier model 560xp, fuel hose is defo older style, connected to carb's intake under the air filter. Not sure about firmware updates.

By refuelling you mean running tank dry and then adding fuel? I topped like a half tank in the morning and it never fired since then.

Compression seems good, measured it earlier today. I have squirted a bit of fuel into intake with syringe and it fired right up, for few seconds anyway. So it's probably carb. I ll take it to shop for diagnostics.

Hello, my 560xp suddenly stopped working. Worked fine other day and today won't even puff. First I have checked plug for spark and it's OK. Problem is that plug is still dry after most vigorous pulling session I have ever done on a saw. Tank->Carb pipes seem OK, fuel is getting into carb. I take it that it have something to do with auto-tune valve. Never serviced one of these newer units, don't know if its possible without diag tools. Anything else comes to mind that I can try to do myself before I take it to shop? Warranty period is long gone. Thanks for possible advice.