I have one of these and I recently lent it to someone. Now when I tried it after a while, it runs for a second or two (if I press the trigger all the way), and then emits a bright spark or two from the motor area and dies. If I release and reengage the trigger, it runs again for about 1-2 seconds and repeats the above. The inside of it looks like below. I took it apart to see if there are any brushes I can easily replace (worn out brushes was a suggestion somewhere on the inter-webs). I don't see any way to access the brushes if this were a brushed motor but this is the first time I have done something like this.
My question is if there is any way to recover this drill? Or is it bound for the junk pile? I realize it is a cheap easily replaceable one but I don't like to throw what I can fix.
Best Answer
So.. I think i fixed it.. this video and others suggest that this might be carbon build up along the shaft of the motor causing the excessive sparking. Some places suggest taking a can of compressed air to the thing.. and I didnt have one so I used a homemade can of compressed air... my mouth.. seems to have worked. The sparks are now down to a minimal level which is apparently expected in a brushed motor, and the drill is able to run even at max speed which it wasnt earlier.
TLDR - Could be carbon build up along the shaft. If you cannot reach the shaft, clean with compressed air or blow hard with mouth.