MS170 will not idle

[Newbie]

I picked up a MS170 (don't laugh it was cheap!! $10) and it started and ran great at full throttle but the min you take the finger off the trigger it dies. I tried to adjust the idle and actually just replaced the carb all together. But I'm still having the same issues. I also have some fuel leaking from the cap and just as soon as I can I am going to put a new fuel cap on. When I replaced the carb kinda looked at the fuel hose but not closely and I don't think a leaking fuel hose would affect the idle as much as it would full throttle performance. Any ideas?  Like I said it was cheap and I am not putting much more into it.

[jteneyck]

Sounds like the tank vent isn't venting.  Try cracking the fuel cap and see if it will idle OK.  You may need to adjust the carb a little or a lot in the process, depending upon where you last left it.  Best to start back at factory settings.  If it idles OK with the fuel cap cracked open, close the cap tightly and see if the problem comes back.  If it does, then you have a bad tank vent for sure.  If so, replace it and you'll be good to go. 

[Newbie]

Thanks I'll look into that. And by "Newbie" I mean I am new to working on and troubleshooting my own stuff. Normally I would have brought my saw in to my local dealer who has a pretty good tech. But this is only $179 saw new and do not plan any heavy work for this saw just a light third saw. Paid $10 and have a $20 carb on it. If I can get it to run well and last a couple of years for under $50 I figure I did pretty well.

[sablatnic]

Maybe take a closer look at the fuel line, they like to crack. Or rather, often does. Crack, I mean. What I would like to say, is, that I have seen several cracked fuel lines on 170, 180, etc.