I have a Sting trimmer Model # TB42CS 4 Cycle, It starts and every time I press the lever to run the attachment it turns over then it just dies and then it takes a few pulls to start again the I go threw the whole process again ( as long as I don't try and run the trimmer, tiller ... attachments it will stay running)

chokes are an obstruction placed over the inlet to increase the vacuum in the carby and cannot be pressed
Primer bulbs are used to suck fuel through the diaphragms to expell all of the air in the system to allow starting
normally press the primer bulb until it is full of fuel
apply the choke and pull until it fires
remove the choke and at full throttle pull until it starts

can u explain little bit clearly?

Adjust your air fuel mixture 1/4 turn at a time until success.

Contact the consumer desk.

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need to adjust the high sscrew. i do mine in 1/4 turns. start machine, full throttle, adjust the h(high) til it clears up.i would start by turning 1/4 counterclock wise, just remember to keep track, in case it runs worse, the put it back to orig. then try the other way. but i suggest 1/4 turn at a time

example... think of a clock when turning screw. straight up and down, 12oc, 1/4 turn will be 3oc, another 1/4 will be 6oc, and so on. hope it helps!

either the carburetor is dirty, not set right or the control lever inside that lets the fuel in isn't set right.

It is unusual for a trimmer to flood itself. It is common to have a lean condition diagnosed as rich.
So lets start by seeing if its lean or rich. Get unit running and apply as much throttle as possible and keep unit running then slowly close the choke. If unit starts to run better as choke is closed then it is lean. If unit dies immediately and is hard to start again it may be flooded.
4 possible reasons for flooding...
1. piece of debris in inlet needle, needle lever adjusted too high
2. adjustment screwd turned too far out
3. exhaust screen clogged
4. low compression
If unit has a stuck inlet needle it will flood while engine is off and be very difficult to start- remove fuel source and/or turn adjustment screws all the way in and pull rope until unit starts ( 4 or 5 times)
clean the carb, screws should start at 1 and 1/2 turns out on the low and 1 turn out on the high.
clean the screen.
If the unit has low compression it is not worth repairing- the cost of repair will exceed the cost of replacement.

First, make sure that the gas mixture is correct (gas and oil mixed in the right proportion). Next, press the primer bulb 3-4 times, turn the choke lever on to Full Choke, and pull the starter cord until the engine seems like to wants to start, but dies. Next, switch the choke lever to Half Choke and start the gas trimmer, giving it gas by pulling on the trigger. Once it has warmed up fully, you may be able to reduce the Half Choke to No Choke, although my 20+ years of experience with dozens and dozens of models tells me that many trimmers run better, although smoking slightly, when you keep them at Half Choke. One last tip, when pulling the cord, try pushing the trimmer away from you with the opposite hand at the exact same time that you are pulling the starter cord--the equal and opposite push-pull technique may sound like something from karate (and it is, in a way), but it is really helpful when trying to start trimmers. Best of luck, Bill

PS: Check you owner's manual (at home or online) for the proper gas/oil mixture. Empty any old gas out and replace the spark plug, if required.

If the trimmer is new and giving you these problems, then take it back to the retailer and either trade for another one, or pay a little extra for a 4 cycle. The 4 cycle is a little hard to start too, but will run out perfectly and no more mixing of oil.

The higher price tag is well worth the time, effort and aggrivation experienced versus a 2 cycle engine.

I hope this helps.

You need to clean the carburetor. Remove and disassemble carb. Use a den Tek Brush, (used to clean between teeth), to clean the small portals in carb. Use a carb. cleaner while cleaning. Make sure the small screen in carb. is free of debris. The smallest of paticles can cause the carb. not to run right. Reassemble the carb. and try starting. If there is no change, then you will need to buy a carb. kit for your trimmer. Replace all appropriateparts: gaskets, diaphragm, needle valve, and the small screen.

Jim