How to Tune up a Small Engine

Tuning a small engine can help the engine last longer and perform better. Bringing it to a repair shop can take weeks and become expensive. Learn how to tune up a small engine yourself and save time and money, while keeping your engine in top shape.

Things You'll Need

  • Screwdrivers
  • Hammer
  • Open-end wrench
  • Feeler gauges
  • Needle-nose pliers
  • Sockets
  • Starter clutch-removal tool
  • SAE 10 W 30 motor oil
  • Oil drain pan
  • Funnel
  • Nut driver
  • Spark-plug wrench
  • Engine tune-up kit (found at small-engine repair shop or hardware store)
  • Begin the tuneup by unplugging the spark-plug wire from the spark plug. Doing this prevents the engine from starting and causing injury.

  • Change the oil. Place the drain pan below the plug; then remove the drain plug, allow the oil to drain, replace the plug and fill the crankcase with oil. Most small engines require 20 oz. of oil.

  • Remove the starter clutch, using the starter-clutch removal tool in the small engine tune-up kit. Once this is removed, you will see the flywheel.

  • Remove the flywheel by putting the wheel puller on the two holes and screwing the shaft until it connects with the crankshaft. Turn the shaft with a wrench until the flywheel is loose. After removing the wheel puller, take the flywheel off the crankshaft and remove the shear pin from it. Set all of this aside until you are ready to reassemble the crankshaft.

  • Use a screwdriver to remove the cover from the points and condenser. With your hand, turn the crankshaft until the points and condenser move as far apart as possible. Remove the screw from the spacer that's holding the points in place, and then the spring. Remove them from the tray.

  • Get the spring compressor from the small engine tune-up kit. Use it to compress the spring and remove all of the wires. Remove the compressor. Install the new points and condenser from the tune-up kit by following the steps in reverse.

  • Use a spark-plug wrench to remove the spark plug. Replace it with a new spark plug , but don't connect the wire until you're finished with the entire project. Make sure to gap the new spark plug according to the manufacturer's directions.

  • Remove the screw on top of the carburetor to find the air filter. Replace it with a new filter and replace the top of the carburetor.

  • Replace all of the parts you removed and start the engine to test it. If it does not start, repeat all of the steps to make sure you are not forgetting something.