What should a two cycle weedwacker sound like?

[LawnBoy97]

I have a ten plus year old craftsman weedwacker with a 23cc engine which runs Pretty good, but at full throttle it sounds a little weird. I am not sure what it should sound like but it just sounds rough. So from idle to full throttle it is a nice whine and then when it is held at full throttle I just doesn't sound right. Is this something that could be fixed with an adjustment screw ^in the carb, owe is it just Because it is old? Thanks.

 

[possum]

Sometimes they do get out of adjustment. Ten years shows good luck or real good care lol. Alot of time the carbs are getting dirty, the diaphrams are getting stiff, the fuel lines about melted, the filter getting gunked up or is just fallen off the line into the tank, the primer bulb is shot etc after a few to several years. Check the plug and the filter screen on the muffler and the air filter if it has one then start looking into the fuel system.

 

[LawnBoy97]

I bought it at a thrift store and i had to replace the fuel line, primer bulb, fuel filter, air filter, and then I went ahead and bought a new spark plug. That's why I was wondering if it was the carb adjustments. But what does the diaphragm do?

 

[scott47429]

there should be a hi end adjustment just use a small screw driver and hold it wide open and turn the screw in a bit and see if that changes anything i have to do that to my sthil weed eater and my homlite chain saw every so often

 

[LawnBoy97]

Do you know where the needle would be or does it depend on the brand of engine?

 

[possum]

It is on the carb. Two screws togather. One is high, one is low. Go to you tube, and type in your weedeater.

 

[LawnBoy97]

I looked on youtube and watched a few videos, not the same model as mine but still craftsman, but I just looked at mine and the only screws I see look like they hold the carb together. I will keep lokking for videos, but I don't know the exact model number. Also, I just noticed that it says 40:1 but I have been using 50:1, so would adding some marvel mystery oil get it closer to 40:1? Thanks.