IF YOU KNOW ANYTHING ABOUT 2 STROKES PLEASE TAKE TIME TO READ THIS POST!

I hope you all can help me with an issue I'm having with my Ryobi string trimmer. I fugure there's got to be someone on here with way more knowledge than me!

It all started with it bogging when I tried to rev it up and it was leaking oil from the muffler. I changed the plug, air cleaner, removed and cleaned the muffler, drained the tank and mixed new premix. Nothing helped any at all.

So next was to check the carb. It looked good and clean. So, I tried adjusting the L&H screws. I'm guessing these are air/fuel mixture.

I finally got it back to running goo. It worked for me a day. Then next time out it wouldn't crank at all. After some fiddling it cranked and ran great. Good for another day! Then it started this crap of acting like it was running out of fuel. It would die every little bit.

So, I tore the whole thing down. I did everything but pull the head and piston. I couldn't find the proper tools to take off the head. So anyways, I took everything apart as far as the carb goes. It all looked good and clean. I sprayed it with cleaner anyways since I had it apart, just for good measure. I removed the intake, which is a piece of plastic that mounts and makes up one side of the crankcase. The metal valve thing on it seemed OK. The piston, rings and pison walls were OK too. Nothing that seemed to be more than normal wear.

This engine is mounted upside down. So the crankcase looked dry other than just a bit of oil on the moving parts. I cleaned everything a little. There was a small mount of black gunk on top of the piston and on the exhaust port. I put it all back together and run those L&H screws all the way in.

From there I just left the air filter off and begain fine adjustments with the screws and kept on pulling. Finally I got it to a place where it started. It ran rough and didn't built RPM's very well. I tried adjusting it more while it was running. I did get some improvement after a lot of adjusting. However, I didn't get it good before it died and it wouldn't crank back.

I was too tired and mad to mess with it anymore for the day. So I gave up. I did notice with the air cleaner off that it was spitting alot of gas through the pinhole in the choke plate when I was trying to crank it. Could that valve in the intake be leaking air back into the carb from the crankcase? I'm at my whits end with this thig. PLEASE HELP![Text

 

You should have check the compression before taking it apart.Sounds like bad rings junk it and get a new one it is cheaper that rebuilding one.

 

Hey Duster, I manage a Sears Repair center that does lawn & garden repair. Ryobi were building some weedeaters for us for awhile, but we quit using them because we had lots of problems with them. The carbs are crap! If the piston is not scored and the base gasket is not blown or the cylinder is not loose, then you will need to replace the carb. spitting gas back out the carb is normal since they are a piston port motor. If this thing has any running time to speak of and you didnt pay too much for it, throw it away and get another one. If it is a high dollar model, then put a carb on it if everything else checks out. Hope this helps,Bubba. PS look at the hard start trailblazer thread in the polaris forum. Do the trick I talk about for compression related problems. Bubba

 

I have had a Ryobi 790 model weedeater for about 4 years... That thing never was too great. It runs OK but takes forever to start - been like that since day one... Those L & H adjustments are what I believe to be low and high speed mixture adjustments.

If it is sounding like it is running out of fuel you may have a sticky float needle??? Also, it never hurts to change the plug and make sure it is gapped properly.

 

As Ftwflh already said, junk it and buy a new one. I had a Ryobi that did the same thing. The repair shop advised me just to buy another weedeater and not get a Ryobi. After buying another brand that has worked perfectly for the past 3 years I realized how bad the Ryobi was.