Revves but wont idle?

[Budget GoKart]

Im probably in the wrong place fir this but i need a little help my dads weed whacker runs and idles but refuses to rev would this missing cause that? Im not skilled with them but neither of us could figure it out but i did get it to run atleast

 

[Smerft85]

Check the fuel line and filter inside the tank, I've had a bad history with those parts. Sounds like a fuel issue of some sort to me.

 

[landuse]

Maybe look at this if you have a Walbro carb

https://www.helifreak.com/showthread.php?t=326599

 

[JTSpeedDemon]

Leaky crankcase seals?

 

[Karttekk]

Find the carb brand and number, pick up a rebuild kit for it. More than likely the diaphragm is split or dried out, that's what pumps the fuel through the carb. Put a new needle & seat in it along with the gaskets supplied in the kit. Once the carb is reinstalled run each mixture screw in slowly until they bottom then turn each one out a turn to a turn and a quarter. This is the initial setting to get the trimmer started. Once it's warmed up set the low and high speed screws accordingly. (Blow some carb cleaner through all of the ports and openings once you take the carb apart.)

 

[Budget GoKart]

Nothing leaks it just doesnt revv it idles great and that screw is missing so i figure that might be the issue. I had the title backwards oops

 

[Karttekk]

Crank seals don't actually leak per se, they dry out and allow air to be sucked through the crankcase causing a lean condition. You're missing either a high speed screw or low speed screw. Check near where the screws are, you'll see either an H or an L stamped in the carb body. Most mower repair/parts shops should be able to come up with one, it needs to be there.

 

[950speed]

Probably the high speed adjustment screw is out of wack, I had the same issue with a chainsaw.

 

[Brianator]

The one screw isnt missing it never came with it, I have a mccollough trimmer lacking it also. I agree with 950speed the about the high speed needle, sometimes you can use a butt connector to make the adjustment, if not cut a slot to use a flathead screwdriver. Hold it wide open while making the adjustment until it's reached a good useable rpm and err on the rich side but make sure you have the spool line out to it's max length to simulate its normal "load" or you'll have a tough time getting it tuned.

 

[950speed]

Well said

 

[Brianator]

Thank you! I tinker with junk often and have learned a thing or few along the way! Lol

 

[950speed]

Thank you! I tinker with junk often and have learned a thing or few along the way! Lol

Exact same here, tinkering has taught me just about everything I know mechanically speaking