Cold Starts

[Likesaws]

My MS 180 and my weedeater runs great but when I start them I have to feather throttle a bit or the die out.
Idle good wot good just die till warmed up. Should I richen up low screw or what is correct fix?
Blower same way all Stihls.

 

[trooney]

Have you set the idle correctly on both and does it change when it warms up? Have you tried leaning out the low side? How long will it idle before it dies? What are the H and L screws set at? Maybe has a small air leak that seals up when it gets warm? Its a little wierd that all three do the same thing.

 

[Likesaws]

Yes they idle great after warm up don't think there is a air leak run great after warm up. Set idle 2900-3100 rpm.
Top' end wot rpm is great. Must be some way I'm tuning it just not sure because runs so well after warm up.
180 has a 025 carb and muff mod.

 

[jmssaws]

To me if your saw isn't cold natured it's fat,yours sound fine to me.

 

[TJ the Chainsaw Mechanic]

Everything will be a bit cold blooded. In my experience with cold blooded saws I have noticed they had troubles when cold because the fuel pump gaskets were starting to stretch, or the diaphragm is getting hard. Both those will cause the saw to run leaner not allow that rich cold start they like. Hence, once warmed up they are fine. Do they sound lean when cold? If so...richen them up a little and raise the idle and see if that helps.

 

[Kevin White]

Does the 180 even have a low speed adjustment? Don't know he could Richen it if he tried. Could it be something with the gas they are all using? Did you buy all at the same time? Maybe they all need maintenance

 

[Frogfarmer]

Your experience is very typical with today's fuel and the EPA regulations the manufacturers have to meet.

 

[huskihl]

I'd say they need 1/8 or 1/4 turn out on the L screw, but the limiters are probably preventing it.

 

[TJ the Chainsaw Mechanic]

Does the 180 even have a low speed adjustment? Don't know he could Richen it if he tried. Could it be something with the gas they are all using? Did you buy all at the same time? Maybe they all need maintenance

The 170 and 180 use the C1Q S57D which has a H/L screw. I've found those carbs to be real picky as far as gaskets go....any stretching or hardening and it's time for new gaskets.

 

[Kevin White]

Good advice, Thanks for the info!

 

[Kevin White]

When you first start them on choke, and it pops, then you move the lever up to high idle, do you let it run for a min like that to warm up or just blip the throttle. I find it helps to let them run on high idle after the choke before I squeeze the trigger. I would adjust the low end an eight to a quarter turn in either direction to see if it improves or worsens, then let us know. If you turn it one way and it falls on its face, you know you've gone the wrong way.

 

[trooney]

I like the idea of turning it out 1/4 turn. That way you can see if it is lean or fat or if it makes it worse or better. Since all three are that way it leads me to believe its a tuning issue not just 1. I have a Husqvarna 50 that way. Warm it runs like the dickens but cold I couldn't even get it to start without putting fuel down its throat and feathering the throttle. Had to richen it up about 1/2 turn and now starts and runs fine. Had the screws originally where they were supposed to be. Had a 180 once too, not a fan of that carb. Too finicky. Never could get mine just right, and thats after a rebuild and a new OEM carb. My Stihl trimmer I have never had a problem with.

 

[trooney]

Ooh, an 025 carb...don't have any experience on an 025 so I couldn't say one way or another. Don't know how that will affect performance.

 

[sunfish]

best to let anything warm up a bit before ya goose it...

 

[MarkEagleUSA]

best to let anything warm up a bit before ya goose it...

That's what she says...

 

[TJ the Chainsaw Mechanic]

My 460's like the throttle feathered a bit during warm up, course I have had them both for several years and have not gone through the carb at all in that time. They have gotten a bit ore cold blooded through time. Also has to do with the idle, mine are set at around 2700 RPM hot. These newer saws seem to be more in the 3000-3300 rpm idle which helps during a cold start. When I've installed new carbs on blowers I've noticed it seems to help a little fattening up the low end a tad because they seemed to have a lean bog off idle....sometimes it works and sometimes it doesn't.

 

[Likesaws]

To me if your saw isn't cold natured it's fat,yours sound fine to me.

I like this answer , just a little ageravtin some times when this happens and they die out, then they can be hard to start.
Thanks

 

[Likesaws]

My 460's like the throttle feathered a bit during warm up, course I have had them both for several years and have not gone through the carb at all in that time. They have gotten a bit ore cold blooded through time. Also has to do with the idle, mine are set at around 2700 RPM hot. These newer saws seem to be more in the 3000-3300 rpm idle which helps during a cold start. When I've installed new carbs on blowers I've noticed it seems to help a little fattening up the low end a tad because they seemed to have a lean bog off idle....sometimes it works and sometimes it doesn't.

Yes it is a new carb may try to fatten up just a little bit. Try to get the best of it without going too far.
Thanks.