1 part 2-stroke oil to 30 parts petrol. To make a tankful put 15ml 2-stroke oil in a container and add petrol to 480 ml. Shake well before putting it in your strimmer. If you have a 1 litre Castrol oil container. commonly used for topping up-cars they have a convenient scale moulded on the plastic bottle. You can used a washed out weedkiller measure for the 15ml. By the way, McCulloch have gone into receivership so it may be worth getting a spare fuel primer bulb while you can. This is the clear plastic dome which primes the fuel pipes prior to starting and is the part which frequently fails because the plastic cracks. Good luck!
Tony Carter
August 2008