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I have a 21" Craftsman push lawn mower with a Briggs and Stratton 7 hp engine that is about 6 years old. I've got it cutting on the highest setting, and it still has issues cutting the grass without loosing rpms in the thicker areas of the lawn. I've done 0 maintence to it besides putting some oil in it this year because it looked low, and actually getting the blades sharpened (that helped immensely), but I still feel like it should be powering through the gas more than it does. What are some steps I can take to improve the power / cutting ability of my lawn mower?

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2 Answers

up vote 1 down vote accepted

Changing the Spark Plug and Air Filter are good ideas, and are general maintenance items. The carb cleaner could also be sprayed into the carb through the intake.

If those items dont restore power, there is a good chance your motor's compression is low - and you need to rebuild it. That could be anything from new gaskets to needing machine work done.

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I would suggest changing the sparkplug and the air filter.Adding some carb cleaner(I'm partial to Techron)to the gas tank.Just add an appropriate amount for the size of the tank.

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Should that help to give the engine more power possibly if they are dirty/worn out? –  Daryl Apr 5 '12 at 15:06
Yes the air filter,if dirty makes the engine run rich(too much fuel too little air) which in turn can foul the plug resulting in a smaller spark.That causes the combustion process to be incomplete.What all this means is your 7hp engine makes 3hp. –  mikes Apr 6 '12 at 0:49
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