First of all, open the jaws of the chuck and look inside. If there is a screw in there you should be able to do this yourself. If there is no screw (sometimes torx/star head, sometimes flat/straight head) then yo uwill need to take it to a service agent/dealer as a special jig is needed to lock the spindle/chuck. If there is a screw you need to remove it. It will be a left hand thread so turn it clockwise to remove. It will be proabbaly be tight as it will be thread locked in the factory. Once this is removed, clamp a 10mm allen key in the chuck adn steady the drill on a workbench. The actual chuck will be a normal thread so this is removed by turning it anti clockwise. It will take a sudden impact to start it off so put the gearbox in a low gear and turn the clutch to 'drill mode'. Holdong the machine steady you can hit the allen key sharply to start undoing the chuck. It may take several hits to get it going.
Answers & Comments
First of all, open the jaws of the chuck and look inside. If there is a screw in there you should be able to do this yourself. If there is no screw (sometimes torx/star head, sometimes flat/straight head) then yo uwill need to take it to a service agent/dealer as a special jig is needed to lock the spindle/chuck.
If there is a screw you need to remove it. It will be a left hand thread so turn it clockwise to remove. It will be proabbaly be tight as it will be thread locked in the factory. Once this is removed, clamp a 10mm allen key in the chuck adn steady the drill on a workbench. The actual chuck will be a normal thread so this is removed by turning it anti clockwise. It will take a sudden impact to start it off so put the gearbox in a low gear and turn the clutch to 'drill mode'. Holdong the machine steady you can hit the allen key sharply to start undoing the chuck. It may take several hits to get it going.