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Discussion Starter #1
The machine doesn't have an adjustable carb and so it runs kind of rough when the temperature is above freezing. Sometimes it will stall and it can be annoying. Short of replacing the carb with an adjustable one is there anything that would help it run smoother until I swap carbs?
 

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You can see if the replacement carb has an adjustable jet.. and see if it will fit your current carb.
I remember your other thread about having another carb... If you still have it you may be able to just use the adjustable jet from it

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They arent interchangeable parts wise, pickup in the carb is different. Whole carb has to be changed when switching from fixed to adjustable jet


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Discussion Starter #4
You can see if the replacement carb has an adjustable jet.. and see if it will fit your current carb.
I remember your other thread about having another carb... If you still have it you may be able to just use the adjustable jet from it

Sent from my LM-Q710.FG using Tapatalk

Great idea! I did not know you could do that. Worth a try and if not switch the whole carb in the springtime. Cheers!
 

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Discussion Starter #5
They arent interchangeable parts wise, pickup in the carb is different. Whole carb has to be changed when switching from fixed to adjustable jet


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That is unfortunate. I guess the whole carb is the way to go...
 

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Is it possible the jet is too large? From what I understand, winter-use machines will have a larger jet than summer-use machines. I got 2 aftermarket (cheap) carbs for my 2-stroke blower, both ran lean and surged. But it's possible the carbs were meant for summer use?

In my case, I opened up the jet slightly, and that helped it run smoother. But if this happens in warmer weather, I wonder if you're running slightly too-rich.

If you can get a new jet, it's possible that would help, if your jet is a bit too-big.

If you have micro-drills, you might try something out-there, like putting a dab of epoxy over the hole in the jet, and re-drilling it slightly smaller. But that's a stretch.

Oh, and another vote for crazzywolfie's question. Understanding if the behavior gets better or worse with partial-choke would help.
 

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Discussion Starter #9
does it run better with the choke closed only slightly open? also any popping out the exhaust?

No popping from the exhaust. I think (not positive) opening up the choke a wee bit helps but usually when I try that it's on the verge of stalling so not sure...
 

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From what I understand, winter-use machines will have a larger jet than summer-use machines.
Exactly, because cold air is denser (more oxygen content per unit volume). You have to enlarge the jet to richen the fuel so the fuel-air ratio is correct for the expected air temperatures. Otherwise the engine will run lean (too little fuel for the amount of oxygen coming in). You can temporarily confirm this effect by closing the choke a little, which offsets the denser air by not letting as much into the carb.
 

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first thing I would check is the choke adjustment. run across many carbs that the choke is partially closed when it is not supposed to be. could also be a leaking needle valve or float adjustment/bad float.
 

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Good point. I've never run into it myself, but if your float is sitting at the wrong height, it will make you run richer or leaner, as I understand it.
 
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