Motor Brushes; Bits; Fasteners - Baumr-AG BMJK-24S User Manual

Bäumr-AG Electric Jackhammers
2. Turn the tool over and drain the oil into a suitable container. It may help hold the tool at various angles to
drain as much oil as possible. Dispose of used oil according to regulations and in an environmentally
responsible manner.
3. Lay the tool flat so the oil sight glass is facing up.
4. Add oil to the tool.
5. Re-install the oil sight glass or plate and seals, then check oil level and adjust as necessary.

Motor Brushes

The electric motor uses 2 carbon "brushes" in order to function. The brushes wear as a result of use – this is
normal, and some tools may come with replacement brushes. If the brushes are allowed to wear past the
acceptable limit, the motor may produce less power, operate intermittently, or not operate at all. To check
brushes:
1. Remove the screws (A) (rotate left) securing the motor brush cover (B) on both sides of the motor
housing (C) and remove the covers. Ensure that any seals (O-rings etc) are retained.
2. Clean the tool in the area under the brush covers to help prevent any dirt or other material entering the
motor housing.
3. Use a coin or wide flat blade screwdriver to remove the brush cap (D).
4. Pull the brush (E) from the cavity and check the length of the carbon section (F). If the brush length is
close to the minimum acceptable limit (7mm), replace the brush – always replace both brushes at the
same time.
A
B
C

Bits

Regularly inspect bits for excessive wear, blunting, cracks or chips. Using a blunt bit will reduce tool
efficiency, and may lead to other problems, such as premature wear in the gearbox or motor brushes etc.
For limited wear or damage at the tip, remove the worn section using a suitable grinder – remove the minimal
amount of material only and be sure to shape the tip correctly. If wear/damage is extensive – replace the bit.

Fasteners

The tool generates a lot of vibration, which may cause some fasteners to loosen over time. Regularly inspect
all visible fasteners for tightness, and tighten as necessary using suitable tools. If the tool vibrates
excessively during use, stop using the tool and check all fasteners before continuing
E&OE
D
F
H
Minimum
= 7mm
©2017 Bäumr-AG
G
5. Insert the brush into the cavity – the brush has
2 prongs on the electrical conductor (G) – ensure
these sit in the slots (H).
6. Re-install the brush cap (rotate right. Do not
over-tighten).
7. Re-install any seals and the brush covers and
secure using the screws (rotate right).
E
10