I got a 18V LI-ion Hammer-Drill Driver off amazon and it worked great for about a week then one day i went to use it and it ran really slow, so i put the battery on the charger, got another one and the same thing happened, as odd as it was i tried one last battery a brand new one, same, went to check the battery on the charger, and it showed the broken battery light, so what happened? and how do i fix my Drill and my batteries?
Think this problem has something with inner core to do. I have similar problem with my corded Horsepower hammer drill. Was once brushing paint off from one wooden cupboard and the revolutions slowed down after 15- 20 mins to ca. 150 rpm as in similar case above and give out some smoke too. Opened it and found out that in the main axis inside the core the metal heart was slightly worn out. Also the two carbon bits (brushes?) connected to the cover were bend slightly backwards due to strong pushing while using the drill. Been planning to oil/ grease the heart on the axis with proper stuff if that would help but trying to figure out other solutions for this problem.
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