If you plan to "mothball" a 2–cycle tool for a long period – say over 30 days or more – a few easy steps will help your equipment be ready for action when you are ready to go back to work.To get the equipment ready for storage, clean it first. The air filter and the cylinder fins can be cleaned by gently brushing them with an old toothbrush.
Remove and examine the spark plug for excessive carbon buildup and adjust the electrode gap to its specification. See instruction manual. You may want to replace it once a year. Carefully reinstall the spark plug, making sure not to cross thread it or tighten too tightly, damaging the threads or breaking the plug. Carefully reconnect the ignition lead.
Check the spark arresting screen. It is a small screen at the muffler exhaust that is usually fastened with a screw or clip. Carbon can build up on the screen. The screen must be cleaned or replaced with a new one.
Standard pump gasoline quickly deteriorates and should not be kept over 30 days in any season. If you need to dispose of fuel mix, please do so in a proper and responsible manner. Small quantities (a quart or so) of STIHL 50:1 fuel mix can be used up in any gasoline engine without a catalytic converter, like a lawnmower, ATV or motorcycle. Remember that all STIHL products use the same 50:1 fuel mix, so the fuel you used for your trimmer will work in your blower or chainsaw, while your trimmer is in storage. It is important to realize that you shouldn’t use the fuel you bought in the fall for next spring. Start each season with a fresh batch of 50:1 2–cycle fuel mix.
Empty the fuel tank. After the tank is empty, if it has a primer bulb, pump the bulb until dry, then replace the cap and start the engine – otherwise, just start the engine. Run it at idle until the engine stops. It is important that the engine is run only at idle speed, so there will be lubrication in the system. Do not operate the throttle or "rev" the engine. Just let it idle until it stops. On a chainsaw, engage the chain brake.
Put it away. For long–term storage, a dry and, if possible, dust– and frost–free place would be ideal. Some equipment can easily be hung on a wall, so you can save space. Store it out of the reach of children.
STIHL recommends STIHL engine oils or STIHL MotoMix® for use in STIHL products.