Switching Gears on your 2-Speed Bluerock concrete core drill 10Z1 10Z1RB 12Z1 12Z1T/S LRBT/S

The 10Z1, 10Z1RB, 12Z1 T/S & 12 Z1 LRBT/S concrete core drills have a 2-speed gear box with straight cut gears which are designed to be stronger but can be harder to engage and need to be perfectly aligned before they will slip into gear. This can be done by rotating the bit by hand until you find a spot it engages, or engage the throttle while turning the gear selector knob as the drill is slowing down. Do not force the gear selector with pliers as it can break. It helps to apply pressure by hand to the gear selector knob while turning the threaded drill spindle, until you can feel it slip into gear and the selector fully locks in gear.