Small Engines (Lawn Mowers, etc.): lawnmower erratic engine, spec numbers, hello jerry

Question
I bought a used McLane 17" selfpropelled 7 blade mower. It has begun to run erratically. With the throttle all the way in, it runs fast-slow-fast-slow, etc. I put in a new sparkplug and the aircleaner is clean. Is this something that I can take care of or does it need to go to the repair shop.  I have tools and am fairly handy.

Answer
Hello Jerry:

From your Description it Sounds like the Carburetor Requires Cleaning. Send me the Model and Type or Spec Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. The Model Numbers May be Stamped Into the Blower Housing (metal engine cover) Above the Spark Plug. Thanks.

Respectfully

John

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Respectfully

John