Milwaukee DescriptionDescriptionDescriptionDescription Service Parts List

EXAMPLE:

00

0

Component Parts (Small #)
Are Included When Ordering
The Assembly (Large #).

SERVICE PARTS LIST

SPECIFY CATALOG NO. AND SERIAL NO. WHEN ORDERING PARTS

M18™ Brushless 1/4" Hex Impact Driver (1 Speed)

CATALOG NO. 2850-20

34

(7x)

60

STARTING
SERIAL NO.

J55A

BULLETIN NO.

54-26-2870

REVISED BULLETIN

WIRING INSTRUCTION

See Pages 2 & 3

DATE

May 2019

61

1 2 3 4 5

45

6 7 9 10

4

35

33

(2x)

37

24

46

7

(2x)

10

2

1

9

3

6

5

48

48a 48b
48c 48d

24

47

48c

48b

36

48d

41

43

49

50

44

35 41
60

51

43
44

FIG. PART NO. DESCRIPTION OF PART NO. REQ.

1 --------------- Front Gear Case (1)
2 45-88-2653 Front Gear Case Washer (1)
3 42-76-0019 Sleeve (1)
4 34-60-0005 Retaining Ring (1)
5 45-88-2026 Washer (1)
6 40-50-0056 Spring (1)
7 02-02-1100 Steel Ball (2)
9 45-88-1547 Washer (1)
10 42-06-2805 Anvil (1)
24 34-40-0595 O-Ring (1)
33 06-82-2367 M3 x 38mm Pan Hd. ST T-10 Screw (2)
34 006-82-6351 M3 x 16mm Pan Hd. ST T-10 Screw (7)
35 --------------- Right Handle Halve - Cover (1)
36 45-24-0260 Shuttle (1)
37 23-28-0400 LED Lens (1)
41 --------------- Left Handle Halve - Support (1)
43 --------------- Belt Clip (1)
44 06-82-2500 6-32 x 5/16 Slt. Pan Hd. T-15 Mach. Sc. (1)
45 14-30-2807 Gearcase/Anvil Assembly (1)
46 14-30-2805 Gear Box Impacting Assembly (1)
47 44-66-2680 End Cap Assembly (1)
48 14-20-2815 Electronics Assembly (1)
48b --------------- Battery Terminal Connector Block (1)

 48c --------------- On-O󰀨Switch (1)

48d --------------- Stator/Main PCBA (1)
49 16-01-2830 Rotor Assembly (1)
50 31-44-2862 Handle Housing Kit (1)
51 42-70-0950 Belt Clip Kit (1)
60 12-20-4107 Service Nameplate (1)
61 42-55-4002 Carrying Case, Standard Equipment (1)

FIG. PART NO. DESCRIPTION OF PART NO. REQ.
62 10-20-4107 Warning Label (Not Shown) (1)

FIG. LUBRICATION
Use Type 'J' Grease, No. 49-08-4220 (1 lb. can)
Service grease may not be compatable with grease used

during manufacturing. 90-95% of the old grease must be
removed prior to any new grease being added.

10 Lightly coat front washer surface of anvil with grease,
place a dab in the ball cavities of anvil.

45 Coat inside of bushing inside front gearcase with grease.

46 NOTE: Do not wash impact assembly. Use a clean, dry cloth
to wipe away any excess grease or contamination.

46 Lightly coat the I.D. of the ring gear and the center of the
planet gears of impacting assembly with grease.

49 Coat pinion of rotor assembly with grease.

MILWAUKEE TOOL l www.milwaukeetool.com

13135W.LisbonRoad,Brookeld,Wisc.53005

Drwg. 2

WIRING INSTRUCTIONS- one of two

NOTE: The pictured rear bearing

area of housing halve may have

changed in appearance

compared to tool being

serviced. This has no
effect on the wiring of

this tool.

Red, white and
black hall sensor wires
(2851-20 only)

STEP 1: Carefully insert rotor into stator. Arrange wires as shown above.
Note the red, white and black wires to the back of PCBA are connected to
the hall sensor, model 2851-20 only. 2850-20 won’t have the hall sensor.

STEP 3: Separate and organize wires as shown above. For the 2851-20,
place three hall sensor wires in bottom of housing halve behind on-off
switch cavity. Place black battery terminal wire over those three wires.

Red, white and black
hall sensor wires
(2851-20 only)

STEP 2: Place rotor/stator and PCBA firmly and squarely in cavities of
left housing halve. Arrange wires as shown above.

STEP 4: Route remaining wires as shown, over the wires from step 3
behind the switch cavity and through the bottom of switch cavity prior to
installing on-off switch.

STEP 5: Place on-off switch firmly and squarely in cavity of left housing
halve. Be sure all previously placed wires are still captured in properly in
wire traps and channels.

Hall sensor
(2851-20 only)

STEP 6: Place battery terminal block and hall sensor firmly and squarely
in cavity of left housing halve. Be sure to capture hall sensor wires in trap
as shown, model 2851-20 only.