Harbor Freight Tools 179cc Owner's Manual & Safety Instructions page 14

Air Filter Element Maintenance
1. Remove the air filter cover and the
air filter elements and check for dirt.
Clean or replace as described below.
2. Cleaning:
• For "paper" filter elements:
To prevent injury from dust and debris,
wear ANSI‑approved safety goggles,
NIOSH‑approved dust mask/respirator, and
heavy‑duty work gloves. In a well‑ventilated
area away from bystanders, use pressurized
air to blow dust out of the air filter. If this
does not get the filter clean, replace it.
Spark Plug Maintenance
Spark
Plug
Cap
1. Disconnect spark plug cap from end of plug.
Clean out debris from around spark plug.
2. Using a spark plug wrench, remove the spark plug.
3. Inspect the spark plug:
If the electrode is oily, clean it using a clean, dry
rag. If the electrode has deposits on it, polish it
using emery paper. If the white insulator is cracked
or chipped, the spark plug needs to be replaced.
Belt Tension Adjustment
1. Turn off engine.
2. Loosen, but do not remove, the four Nuts (21) that
hold the Engine (16) to the Connecting Plates (23).
Belt Replacement
1. Turn off engine.
2. Loosen, but do not remove, the four Nuts (21) that
hold the Engine (16) to the Connecting Plates (23).
3. Using Nut (43) and Bolt (42), slide the
Engine (16) towards the Driver Pulley (47)
until Belts (20) can be removed.
4. Remove the old Belts, then install new ones.
Page 14 For engine technical questions, please call 1-800-520-0882.
For other technical questions, please call 1-800-444-3353.
• For foam filter elements:
Wash the element in warm water and
mild detergent several times. Rinse.
Squeeze out excess water and allow it to dry
completely. Soak the filter in lightweight oil
briefly, then squeeze out the excess oil.
3. Install the new filter or the cleaned filter.
Secure the Air Cleaner Cover before use.
NOTICE: Use only the spark plug listed on
the Technical Specifications chart. Using an
incorrect spark plug may damage the engine.
4. When installing a new spark plug, adjust the
plug's gap to the specification on the Technical
Specifications chart. Do not pry against the
electrode, the spark plug can be damaged.
5. Install the new spark plug or the cleaned spark plug
into the engine. Gasket‑style: Finger‑tighten until the
gasket contacts the cylinder head, then tighten about
1/2‑2/3 turn more.
Non‑gasket‑style: Finger‑tighten until the plug
contacts the head, then tighten about 1/16 turn more.
NOTICE: Tighten the spark plug properly.
If loose, the spark plug will cause the engine
to overheat. If overtightened, the threads
in the engine block will be damaged.
6. Apply dielectric spark plug boot protector
(not included) to the end of the spark
plug and reattach the wire securely.
3. Slide the Engine (16), away from the Driver
Pulley (47), until the belts are properly tensioned.
4. Tighten the four Nuts (21) that hold the
Engine (16) to the Connecting Plates (23).
5. Check the alignment of the two pulleys
(side by side ‑ in the same level/surface).
6. Using Nut (43) and Bolt (42), slide Engine (16) away
from Driver Pulley (47) until Belt is properly tensioned.
7. Re‑tighten the four Nuts (21) that hold the
Engine (16) to the Connecting Plates (23).
Item 69086