How to change hitachi Wh18dl impact driver brushes

Generally the answer is yes for most models. Check the manual.

I think that model is on a ring internally so there isnt a way to do like the bigger ones, you would have to take the screws out and take in half and you will the the brushes and can replace.

Sounds like the armature in the motor has a problem. Check the brushes too.

When that happened to one of my drills, it turned out that the connection up inside the handle where the battery connects to the drill needed to be cleaned. I also had to use a screw driver to slightly bend the connectors inward (away from the side) on the inside so the battery would make a better connection. If that doesn't solve the problem, they there is most likely a loose connection in the switch or wires leading to the motor. I have never had the brushes go out on a battery operated drill so I would start with checking the battery connection first..

Make sure it's all the way in gear. It sounds like it's not all the way in first or second gear. Yes it sounds dumb, but it's one of the most common problems we see in our shop.

sounds like your brushes need a look at remove to see if broken or worn and replace them

Brushes on the side may be worn buy new ones and change them

It sounds to me as if the electrical contact brushes on the motor are worn out and need replacement.
You can contact a retailer such as the ToolBarn at 1-866-597-3850, sales(at)toolbarn.com.
Or Hitachi directly:
https://devs.hitachi-koki.co.jp/ois/login.html?te-uniquekey=12ea37192ba

Hi Mark,
R8 Should be a 1000 Ohm 1/4Watt resistor
Rgds Ray

Depends on model you have. There are 2 brushless models - BTD132 (14.4V) and BTD144 (18V) - both have big BL letters on housing. According to your picture, you have BTD140 which has brushes. When you open user manual, you can find section dedicated to changing brushes. In case it does not help, you migh want to check trigger. Juraj