Harbor Freight Tools 68120 Recommended Spark Plugs, Air Filter Element Maintenance, Cleaning

SAFETY

SETUP

OPERATION

MAINTENANCE

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.

•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.

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.

Recommended Spark Plugs

Brand
	68120, 68121	68136	68306
NGK®	BP-6ES
NHSP® / TORCH®	F6TC	F6TC	F6TC

NOTICE: 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.

Page 16 For technical questions, please call 1-800-520-0882. Horizontal Engines