2 cycle trimmers that are run with gas(no oil) usually are destroyed within a couple minutes of running. If the motor still turns when you pull the starter cord you may be able to save it. Remove the spark plug from the top of the motor. Spray a burst of WD40 into the spark plug hole. Let theWD40 penetrate for a few minutes. Pull the cord a few times to get the WD40 worked into the motor. Hopefully, when you drained the old gas, you let the gas evaporate from the supply lines. Replace the spark plug fill up with gas/oil mixture and try to start the machine. Let it run without revving it too high for a few minutes. You will probably have a 50/50 chance of it working fine or the motor will seize up.
Mikeohh, June 2007