Sears self propelled 4.75 sputters?

Question

It starts fine first pull, runs awhile then starts "hunting" for a fast then slower speed, then fast again. During this cycle it will puff black smoke then run normal then puff black smoke. This only happens after it runs five minutes never at first start up.

Out of nowhere it started this, any ideas? Thanks

Answer 1

Trade it in for a John Deere,

Nothing runs like a Deere.

Answer 2

Sounds like you need to change your air filter. A clogged air filter will make it run rich....

Answer 3

The carburetor needs cleaning and a rebuild kit installed.  If this is the type of carb that sets on the fuel tank there is a diaphram between the two.  You can replace the diaphram for about $5.00..  It is an easy job.  Just watch how the rods and springs attach to the carb before you take it off.