Depressing the throttle slightly we listen to the engine. If the engine hesitates to accelerate, the LO screw should be opened 1/8 of a turn. If we open the screw too much, the engine will not accelerate smoothly and start shaking (too rich of a mixture). In this case we should close the LO screw slightly. We repeat this procedure until the engine reacts smoothly when adding power. Meanwhile, a readjustment of the idle speed may be needed.
After the LO mixture has been adjusted, we proceed with the HI screw adjustment. After securing the paramotor, we open the throttle to full power. We turn the HI screw to the left or right until the maximum RPM is reached. From this position just a slight turn to the right should cause a significant RPM drop. This means the lean side of the mixture has been achieved. Immediately we OPEN the screw to the left to prevent the engine from overheating!
Let us repeat once again this critical step:
At full power we tune for maximum RPM, then we close the HI screw more, until a drop in RPMs is noticed. When the drop in RPMs occurs we open the HI screw again until we reach maximum RPMs once again, and then we open the screw more until we have a drop of 20 to 60 RPMs. In this position the carburetor will be perfectly tuned slightly on the rich (safe) side.
Next, we should close the throttle and recheck the idle and the LO screw adjustment. If the carburetor was tuned properly, the idle will return to the normal setting described above.
To put it in a nutshell, if the engine idles and accelerates smoothly, does not smoke heavily and achieves 20- 60 RPM below maximum RPM, the carburetor is tuned correctly.
SOURCE: I need help with a carburetor adjustment on my chainsaw.
this site gives alot of helpful hintshttp://www.arboristsite.com/showthread.php?t=5208
SOURCE: husqvarna chainsaw carburetor adjustment
Find the 2 screws. There will be a (h) high and (L) low. These are for hig rpms and low rpms. First tighten the screws. Then unscrew them about 1-1/4 turns. Then start the saw and let it warm up. Start with the high rpms first pull the trigger all the way then adjust the screw in 1/8 turns either way until it is running good at high rpms. Then work on the L rpms. Get the saw to idle then pull the trigger, there should not be any hesitation when going from L to H rpms. Just adjust the low same as the High. They have to work together so if the high is good and the low is not just right turn the h a small amount. If you have any more questions let me know
SOURCE: adjusting carburetor
Does saw try to run? Initial settings are about two turns out from CW stop. Set high speed (on warmed up engine) to 4-stroke with no load, but smooths out with light load (cutting wood). Idle is set for fairly smooth idle, but engine picks up with throttle without lag. Idle speed setting is somewhat below chain drive clutch pickup, but allows engine to keep running.
SOURCE: what is the carburetor metering lever adjustment for an
Clarification Request
Posted by slohry on Apr 10, 2009
What kind of carburetor does it have? Zama, Walbro? And what model carb?
No response to clarification request... delete this question.
SOURCE: carburetor tool
Unless you are skilled enough to make your own, you are stuck taking the saw to a servicing dealer as they are the only ones allowed to possess the necessary 'D' head screwdriver. Give thanks to the EPA for mandating the prevention of mal-adjustment pollution.
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