Hitachi Drills - Page 3 - Recent Questions, Troubleshooting & Support

There are always 2 different rings to the chuck grip surface, you always hold the back one and turn the front one counter clockwise.
You should be able to do this by hand.
But if it is really tight for some reason, you could use a channel lock pliers or even a pipe wrench if you had to, but both might leave some marks.

Need to know the model you have. The larger Hitachi hammers have external brush caps (usually under a metal plate or metal end cover)

I've followed HELP2DIY's advice 4 #3 phillips screws will open the case there are actually 2 fuses 15A glass type which i can see that both wires through the visible glass are intact the rest of the resistors and capacitators & what-not on the circuit board/ breadboard also show no signs of any electrical burns i've also have 2 replacement batteries just to test this charger & still blinking any others found a way to fix this "made in china" product? i also went to AzOn for similar reviews with no real answer but to just buy another one

Replacement Hitachi 12v Batteries Replacement hitachi 12v batteries HITACHI 12V Battery Replacement Cordless Drill Battery 12V Hitachi

Please check the LED status of the charger to find out what the reason and solve it.

It's burnt up, best to replace it.

Sounds like a battery problem. Try getting a new or better yet a rebuilt battery for it and see if the speed doesn't come back. Your battery maybe worm out and unable to give the same power it did when it was new.

http://www.amazon.com/HA13001-Power-AMP-1x17-5W-18V/dp/B00EUBHERM