Problems with carburetor on stihl 193t when it gets hot...??

[Tree94]

I got a stihl 193t that always acts up when it gets hot.
I live in Tucson, AZ, during summer the temps are in the 100's.
In the morning, the saw starts right up and runs good.
But later on during the day, the saw has trouble starting and dies out when I give it gas.
I try to adjust the carb and lean it out since im thinking the heat is making it run rich.
It helps, but the saw still runs like ****!

Sometimes, the saw also will only run when I hold it on its side.
I thought these 2 stroke saws are made to operate any way you hold it? (upside down, pointed straight up, pointed down..)
But it only happens to my 193.
Ive got a 391, 290, 660, and they all run good. But my trim saw always gives me problems...

The saw is less than 1 year old.
Any advice?
Thanks,
Russ

 

[mountainlake]

When it dies when you give it gas it's lean, try adjusting it richer. Most likely vapor locking(fuel too hot) set it in the shade and let it idle a bit to cool down. Steve

 

[Chris-PA]

The symptoms don't really sound like vapor lock - usually that manifests as very hard starting after shutting it off for a while and letting it heat soak. Often full choke is required to restart when hot. However, once they get going again they run fine, although they may fart around for a bit right after restart until the intake and blower air cools the carb.

 

[mountainlake]

The symptoms don't really sound like vapor lock - usually that manifests as very hard starting after shutting it off for a while and letting it heat soak. Often full choke is required to restart when hot. However, once they get going again they run fine, although they may fart around for a bit right after restart until the intake and blower air cools the carb.

Did you read that it starts hard and dies when giving it throttle, no need to contradict good advice is there. Unless you just want to be a $%^% Steve

 

[Chris-PA]

Did you read that it starts hard and dies when giving it throttle, no need to contradict good advice is there. Unless you just want to be a $%^% Steve

My explanation of how vapor lock behaves and when it occurs was intended to reduce confusion. Vapor lock causes hard starting after extended heat soak when the saw is shut off. It can cause some short term running issues while trying to get it going again, but these go away once the fan gets going and cool air is pulled through the carb. It has zero effect on how the saw runs after that at all. It doesn't change how the saw runs when you turn it on the side, etc.

It's possible the OP meant it only misbehaved for a short time after he got it running again, but it isn't written that way - and therefore it's not likely to be vapor lock and your "good advice" was more likely to be a distraction. I could have said that initially, but I figured I'd just let the explanation stand for itself and those reading could decide for themselves. Naturally you turned it personal.

 

[lone wolf]

Could be the coil, Could be a crank seal.

 

[rd35]

Coil or crank seal was what I was thinking too!!!

 

[backhoelover]

could test tank vent also

 

[Tree94]

So I figured it out.
The LA screw was running WAYY to rich...
I'm not sure how that happened. I'm wondering if it vibrated loose because I don't recall setting it that rich..
Anyway, running a lot better now. Thanks for the replies..

 

[lone wolf]

So I figured it out.
The LA screw was running WAYY to rich...
I'm not sure how that happened. I'm wondering if it vibrated loose because I don't recall setting it that rich..
Anyway, running a lot better now. Thanks for the replies..

LA cant make it run rich that is an idle setting. H and L can though.

 

[lone wolf]

 

[Tree94]

LA cant make it run rich that is an idle setting. H and L can though.

the LA was set way loose.
Which I thought meant that too much gas was being let out at idle??
making it run rich?
maybe im wrong.. lol
either way, that's what the problem was