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Can you tell me the initial carb mixture screw adjustments and which screw is the Hi or Lo, left or right? Have been looking for an online operators manual with no success yet. Thanks.
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That is the mixture screw. Turn clockwise to get a leaner mixture, counter-clockwise for richer. For initial setting, try with the mixture screw open 1/4 turn. Start the engine and adjust the mixture screw for good running. After it is warmed up, lean the mixture until the engine starts to miss and then turn the screw about 1/8 turn CCW
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.
Regarding the adjustment procedure you generally start your low and high mixture screws at one turn from seat, or slowly turn them in all the way until they bottom out and then back them out one full turn. You will adjust the high speed mixture screw at full throttle and get the median point between too rich (loads up) and too lean (dies out). You will want to do the same thing with the idle mixture screw, just adjust at idle rpm. You will also adjust the low idle mixture screw to give you a smooth transition from idle to throttle up. Once this is obtained, you adjust the third or idle speed screw low enough so the chain does not turn at idle rpm but high enough so the saw doesn't cut off. Hope this gets you going.
if its the carb screws your talking about
one it for fule mixture the other is for air,,,
air for tickover fule mixture for rev's
if its running well leave them be?
your mixture screws probibly have to be adjusted.i have a homelite weed whacker and homelite leaf blower.
both had to be adjusted after i used them 6 or 7 times.theres a tool you can buy to move the screws.or you can be cheap like me and use a dremal tool with a cutting wheel on it and cut slots in to be able to adjust with a flat head.
turn the screws clockwise til there just seated,not too tight.then turn each one out counter clockwise to 2.5 turns and start adjusting from there.the first screw is the low setting and the second is the highs. i usally start with the highs.but u can do what you want. u can also youtube on how to adjust.
air fuel mixture screw shoould have initial setting of two turns out from lightly seated,check unit make sure cylinder is tight to base they only have two screws holding them down,if 2 cycle motor has a vaccum leak they will not run properly,also check compression if you have gauge should have a least 100 psi to run properly.
Start with 1 turn out from bottom on both and adjust from there as needed. The screw closest the engine is low speed mixture adjustment and the outer is high speed mix. adj. Hope that helps. Dwain
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