How to Repair a Troy-Bilt TB70SS

Clean the Air Filter

• 1

  Loosen and remove the four screws holding the filter cover in place using a flat-blade or T20 Torx bit screwdriver. Remove the cover, taking care not to force it off, as this may damage either the cover or the engine.

• 2

  Remove the air filter from the cover and wash it in a mix of water and detergent. Rinse the filter, then squeeze it to remove excess water. Allow the filter to dry completely.

• 3

  Lightly coat the filter in clean SAE 30 oil. Squeeze the filter to remove excess oil and to ensure the entire filter is coated.

• 4

  Place the filter back inside the cover, then put the cover back in place. Tighten the four screws with a screwdriver and secure the cover in place.

Replace the Spark Plug

• 5

  Turn the trimmer's engine off and allow it to cool. Once the engine cools, remove the spark plug wire from the spark plug.

• 6

  Clean the area around the spark plug with a cloth. Turn the spark plug counterclockwise with a 5/8-inch socket to remove it.

• 7

  Set the air gap of the replacement plug at 0.020 inches using a feeler gauge. Put the spark plug in place, then use a 5/8-inch socket to secure the plug. Turn clockwise to tighten, though do not over-tighten.