Hot weather chainsaw tuning??

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The MS 362 I use for one of my jobs runs well all winter and summer without re-tuning.
Yeah, for some odd reason, I never need to adjust the carb on my 361. My 660, on the other hand, needs a lot of babysitting. Both have muff mods...and I use non-ethanol gas for both.
 
I talked to mechanics at two local shops and they never heard of winter gas issue or saws needing to be tuned according to the season. I can only think they didn’t know what was causing the problem and just fixed the issue.
 
I have quite a few saws, and really only have 3 that are rune snobs. The 346xp (ported) is very temperamental, I actually attribute this to being one of my very first port jobs. My 359 is kinda picky. It deffinatly needs a winter and summer tune, but other then that is spot on for the season. My 394xp is a little picky too. I actually just let it set on its winter tune, as unless I get a real big tree to drop, it's just on mill duty. My 390xp doesn't really seem to care too much about the weather for some reason. I have tweaked it here and there but doesn't seem to make a huge difference either way.
 
One guy did say something about saws being tuned based on where in the world they’re sold.
So, my plan is to get new gas and if won’t start once hot I’ll tweak the low setting.
 
Ok... Ignoring the last few posts & attempting to get back on topic...
Winter fuel won't be doing you any favors so avoid it if possible. Ideally run a little extra oil (40:1 quality synthetic) & tune a bit rich.
Don't up the oil without tuning it for the mix you intend to run. Tuning should ideally be done with a tacho & in your case (new saw, hot running) set to a few hundred rpm below max.
Madsen's has some good directions on tuning by ear. In a pinch you could probably just turn the H screw OUT 1/8 of a turn. Your adjustment screws may be tamper proof, may have limiters on them, making adjustments may void your warranty & if you get it wrong you may wreck your saw.
Good luck :)
Is this an H problem or an L problem or both? If it’s not starting hot tweaking the L is what will get it going?
 
Bad gas, winter gas, summer gas, etc. Its usually an excuse people make when they don’t know what the real problem is. I’ve run gas over a year old and nary a problem was had. If it’s in a sealed can with good mix it’s not going to go stale, the oil isn’t going to fall out of suspension. It’s not going to magically drop octane. Gas in an unsealed can goes bad because the good stuff in it evaporates and that makes Al Gore and Greta cry. So do the world a favor and make sure your gas can is sealed.
 
Bad gas, winter gas, summer gas, etc. Its usually an excuse people make when they don’t know what the real problem is. I’ve run gas over a year old and nary a problem was had. If it’s in a sealed can with good mix it’s not going to go stale, the oil isn’t going to fall out of suspension. It’s not going to magically drop octane. Gas in an unsealed can goes bad because the good stuff in it evaporates and that makes Al Gore and Greta cry. So do the world a favor and make sure your gas can is sealed.
Well don't forget different regions of the Country have different blends! I can guarantee you that winter gas is a problem here when it gets hot?
 
Maybe but I’ve never noticed a difference after years of two stroke dirt bikes and chainsaws and weed eaters. I live in northwest Washington state.
 
I put gas in that’s working fine in 2 other saws and had the same problem. I tweaked the L and got it running better.

Why is winter gas considered the more likely culprit than a incorrectly tuned saw?
 
Maybe but I’ve never noticed a difference after years of two stroke dirt bikes and chainsaws and weed eaters. I live in northwest Washington state.

I put gas in that’s working fine in 2 other saws and had the same problem. I tweaked the L and got it running better.

Why is winter gas considered the more likely culprit than a incorrectly tuned saw?
Its that time of year where there is some winter gas is still around and it is getting hot is why. Once all that winter gas is used up soon there wont be so much trouble. When 2 or three saws or blowers or whatever act up at the same time you can bet its gas.
 
Bad gas, winter gas, summer gas, etc. Its usually an excuse people make when they don’t know what the real problem is. I’ve run gas over a year old and nary a problem was had. If it’s in a sealed can with good mix it’s not going to go stale, the oil isn’t going to fall out of suspension. It’s not going to magically drop octane. Gas in an unsealed can goes bad because the good stuff in it evaporates and that makes Al Gore and Greta cry. So do the world a favor and make sure your gas can is sealed.
Gasoline is like milk. No matter how tightly sealed, it's going to go bad. 10x more so for ethanol blended fuel.
 
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