Chinese carb question

[ipbr21054]

Morning,
Please see attached photo.

If the silver screw is for tickover then would that mean the brass srew is the mixture ?

If so please advise how its set up.

A strimmer starts fine but when using you need to have the choke lever on a touch otherwise it stalls

 

[Burnerman]

The brass screw is for the slow running mixture, the silver for tickover speed.
These carbs have a variable main jet....as the throttle is opened, there is a needle that rises out of the jet - it is adjustable but it's very rare to do so.
Once more, there is likely to be a tiny fuel obstruction somewhere but I'd only recommend opening these carburettors unless you have a diaphragm / gasket set to hand.
However, try turning the brass screw 1/4 turn anticlockwise.
The carb is likely to be a Ruixing make - very similar to a Walbro but the parts aren't interchangeable.
John

 

[ipbr21054]

So how do I adjust it so when I use the trigger to Rev it,

1 I dont need to use choke.
2 It doesn’t bog down etc.

when it was running fine you can hear that lovely whir or the line slicing through the air.

 

[Burnerman]

Set the slow running speed using the silver screw if you can.
Then adjust the brass screw. Turning in should cause the engine to speed up, then turn back until the engine slows down. Too far and the engine will run on the rich side so its clockwise again until it runs smoothly and picks up well. A good starting point is 11/8 turns out from fully in.
John

 

[ipbr21054]

Is that with throttle trigger left alone or held down so revving ?

 

[Burnerman]

See if you can get the machine running on the silver screw without using the trigger, then back it off so its running pretty slow. If the machine has a centrifugal clutch then it needs to be slow enough for the reel not to rotate.
John

 

[ipbr21054]

ok thanks