Home > Lawn & Garden > Home Gardening > Equipment > Hand Tools > Spark Plug Tightening Torque It is very important to properly tighten spark plugs after replacement or cleaning – especially on small engines with aluminum heads. This table gives approximate torque values for different sizes of spark plugs in both cast iron and aluminum heads. Torque Wrenches [Image: Exposed pointer type torque wrench] If you plan to do much work on lawn/garden or grounds maintenance equipment, you need a torque wrench. Even a job as simple as changing a spark plug on a small engine should be done with a torque wrench. Wrenches [Image: Basic wrenches] The most basic tools needed for working on lawn and garden equipment are wrenches. You can sometimes get by on other little fix-it jobs around the house with pliers, screwdrivers, etc., but almost anything you try to do on grounds maintenance equipment will require the use of wrenches. Tools For Maintaining Lawn And Garden Equipment [Image: Basic tools] If you own lawn and garden equipment, you will probably need a few tools for maintenance unless you plan to return the equipment to the dealer every time something is needed. A few basic tools will allow you to do many jobs.  more articles... Bolt Tightening Torque When tightening bolts on your equipment, it is sometimes helpful to know the recommended torque. If so, this table should help you. More Ways To Get A Handle On Garden Tools Most garden tools have fixed handles that may be made of wood, fiberglass or metal. But an LSU AgCenter engineer says some tools now are available with separate handle and toolhead components that can be interchanged as desired.