Weed trimmer engine problem

[Carlos motors]

So I bought used weed trimmer engine and problem is every time I start it, after few times pulling rope, it runs for a second or two and then dies. When I somehow start it by moving gas lever with other hand it runs okay. And it is NOT IDLE SCREW. I adjusted idle screw fine. Choke lever is also as it should be and only screw i have left is I think gas screw which I also moved but no so much results. Also I cleaned whole carb and air filter.

 

[Carlos motors]

This is screw you move it by putting nail or something in small hole that you see.

 

[Steve Best]

Hi Carlos, that is a not an idle speed screw.
It should be on the other side of the carb and look like this pointy screw on the right:

http://www.homeandautorepair.com/ho...carburetor-–-2-cycle-or-4-cycle-carb-rebuild/

http://www.letterkennymodelflyingclub.com/walbrotuneup.htm

 

[Carlos motors]

Hi Carlos, that is a not an idle speed screw.
It should be on the other side of the carb and look like this pointy screw on the right:

http://www.homeandautorepair.com/how-to-rebuild-and-clean-a-weedeater-or-lawnmower-carburetor-–-2-cycle-or-4-cycle-carb-rebuild/

http://www.letterkennymodelflyingclub.com/walbrotuneup.htm

Yes I know. The screw on photo is I believe gas screw.

 

[5-7HEAVEN]

Yes I know. The screw on photo is I believe gas screw.

It looks to me like a plug for the fuel passage.

On automobile carburetors, they use lead shot as fuel plugs.

Like Steve mentioned, tighten the pointy screw to raise your idle speed.

 

[Street Ryderz]

This is screw you move it by putting nail or something in small hole that you see.

In the small engine repair shops that screw is reffered to as a Pac Man screw (valve) and the manufactures use them so that consumers have to use their service centers or an authorized dealer for repairs or even a tune up!They have a propriatary tool to adjust the needles(valves) you can buy the tool but it has to be ordered and it's not cheap as they know if you order the tool they are losing money!The poor mans way is to slot the head of valve with a rotary tool and small thin cut off disk so you can use a flat head screw driver to adjust it!BTW you will most likely have to cut into the body on etheir side of the cut in valve! those little cuts have no effect to the carb.

 

[Carlos motors]

In the small engine repair shops that screw is reffered to as a Pac Man screw (valve) and the manufactures use them so that consumers have to use their service centers or an authorized dealer for repairs or even a tune up!They have a propriatary tool to adjust the needles(valves) you can buy the tool but it has to be ordered and it's not cheap as they know if you order the tool they are losing money!The poor mans way is to slot the head of valve with a rotary tool and small thin cut off disk so you can use a flat head screw driver to adjust it!BTW you will most likely have to cut into the body on etheir side of the cut in valve! those little cuts have no effect to the carb.

Well i found a tool and I can adjust it but the thing is that screw has been in severak different spots/positions and I didnt have luck. Also when I tighten it that is less fuel and when I unscrew it that is more fuel?

 

[Carlos motors]

It looks to me like a plug for the fuel passage.

On automobile carburetors, they use lead shot as fuel plugs.

Like Steve mentioned, tighten the pointy screw to raise your idle speed.

Idle speed is not the problem because when I am pull starting it I also put throttle in several positions 1/4,1/2 and I never know what is sweet spot to starting it. You start it on 1/4 throttle it runs for 2 seconds and dies again same throttle position everything same and you can try 20 times it wont start. So I start it succesfuly somwhere around 10-15 tries.

 

[Street Ryderz]

Well i found a tool and I can adjust it but the thing is that screw has been in severak different spots/positions and I didnt have luck. Also when I tighten it that is less fuel and when I unscrew it that is more fuel?

That one is most likely the high speed adjustment! the low speed is metered in the body and may not even be adjustable,You may want to take it apart and check that the diaphram is not cracked and functions properly and that fuel is going thru all orifices and metered passages properly the link Steve provided has some good info for that style carb!

 

[Carlos motors]

That one is most likely the high speed adjustment! the low speed is metered in the body and may not even be adjustable,You may want to take it apart and check that the diaphram is not cracked and functions properly and that fuel is going thru all orifices and metered passages properly the link Steve provided has some good info for that style carb!

I cleaned carb with gasoline and nothing is cracked. Maybe I need to clean it also with compresed air. And again question: When I tighten that screw do I get more or less fuel?