Hitachi DS18DSAL Instruction Manual - Page 17

English MAINTENANCE AND INSPECTION CAUTION ⅷ Pull out battery before doing any inspection or maintenance. 1. Checking the condition of the bit The bits should be checked regularly. If worn or broken bits can slip or decrease the efficiency of the motor and burn it out. Replace worn bits with new ones. CAUTION ⅷ If you use a driver bit of which point is worn or broken, it will be dangerous since it slips. So replace it with a new one. 2. Check the Screws Loose screws are dangerous. Regularly inspect them and make sure they are tight. CAUTION ⅷ Using this power tool with loosened screws is extremely dangerous. 3. Maintenance of the motor The motor unit winding is the very "heart" of the power tool. Exercise due care to ensure the winding does not become damaged and/or wet with oil or water. 4. Inspecting the carbon brushes (Fig. 13) The motor employs carbon brushes which are consumable parts. Since and excessively worn carbon brush can result in motor trouble, replace the carbon brush with new ones when it becomes worn to or near the "wear limit". In addition, always keep carbon brushes clean and ensure that they slide freely within the brush holders. Nail of carbon brush Protrusion of carbon brush Fig. 14 5. Replacing carbon brushes Take out the carbon brush by first removing the brush cap and then hooking the protrusion of the carbon brush with a flat head screw driver, etc., as shown in Fig. 15. When installing the carbon brush, choose the direction so that the nail of the carbon brush (See Fig. 14) agrees with the contact portion outside the brush tube. Then push it in with a finger as illustrated in Fig. 16. Lastly, install the brush cap. CAUTION ⅷ Be absolutely sure to insert the nail of the carbon brush into the contact portion outside the brush tube. (You can insert whichever one of the two nails provided.) ⅷ Caution must be exercised since any error in this operation can result in the deformed nail of the carbon brush and may cause motor trouble at an early stage. NOTE: When replacing the carbon brush with a new one, be sure to use the Hitachi Carbon Brush, Code No. 999054. Wear limit Fig. 15 0.12" (3mm) 0.45" (11.5mm) Fig. 13 Contact portion outside brush tube Fig. 16 17