stihl fs 55 rz trimmer wont run wide open, and floods out.

[Hersheyfarm]

I have had this thing for almost 10 years with no probs at all till now. It flooding out and not hitting top rpms. Now it will not hardly run. I have cleaned spark arrestor, new plug, cleaned muffler, air filter. Took spark plug off and muffler and made sure no fluid in crankcase. It will start but will not hit hi rpms and will flood out. Carb is next on list but just checking here incase this is a common issue.

 

[beenthere]

You said you cleaned the muffler, and that would have been my first guess as to the problem. Are there a couple holes that you can twirl a twist drill bit down through to clean out the carbon? Has usually worked for me.

Any suspicion of the fuel and fuel mix?

 

[randy41]

check the fuel filter and the fuel pickup line.

 

[gauthier]

At 10 years old,assuming you've done the required maintance on it all along,could be a cracked line or leak in around lines.