Chicago Electric MIG 170 Owner's Manual & Safety Instructions page 11

7. Turn the Feed Tensioner knob counterclockwise to
loosen it enough to pull it down to remove tension.
(Do not loosen the Tensioner knob too much, or the
Tensioner will come apart.)
Then, swing the Feed Swing Arm up.
8. Feed Roller Instructions:
Check that the Feed Roller is turned to properly
match the wire size marked on the Wire Spool:
A. Twist the Feed Roller Knob about 1/3 of a
turn counterclockwise  until it stops.
B. Pull the Feed Roller Knob straight
off to expose the Feed Roller.
C. Flip the Feed Roller as needed and
confirm that the number facing you is the
same as the wire diameter on the Spool.
(0.8mm = .030" & 0.6mm = .023")
D. Place the Feed Roller Knob back into place in
the same orientation it was removed in, and twist
it about 1/3 of a turn clockwise to secure it.
SKU 68885 For technical questions, please call 1-800-444-3353.
Feed Feed Swing
Tensioner Arm
Feed
Roller
Knob
C
A
Feed
B
Roller
D
Page 11