Slightly loosen the Gearbox Clamping Nuts. If machine is fitted with aluminium front Chain Cover it will be necessary to loosen the Nut which holds the Chain Cover at the back of the Gearbox. Now move the Gearboxalong by means of the Adjusting screw below the Bracket supporting the Gearbox. Always finish the adjustment by tightening the adjusting nut, so that it tends to push the Gearbox towards the Engine. This will prevent the Gearbox slipping and possibly tightening the chain when the machine is in use. To do this, turn the nut anti-clockwise. This is best done after the Clamping Nuts have been tightened up.