(3) Show signs of having been overheated, as evidenced by: melted babbitt, smoking
from hot oil, or journal surface damage.
(4) Have a broken back or lug.
(5) Are worn 1/4 inch or more lengthwise at either end.
(6) Have a combined wear lengthwise of 3/8 inch or more.
(7) Have a lug worn to depth of 1/8 inch or more in area which is over 50% of contact
(8) Have combined wear, on both sides of lug extension is 1/4 inch or more at any
(9) Have a lug worn through to brass at any location 3/8 inch or more above the lower
edge of brass side walls.
c. Defective plain bearing wedge. See Figure A- 3 for an illustration of a plain bearing
wedge. Plain bearing wedges are defective and shall be replaced if they:
(1) Are missing, cracked, broken, or bent.
(2) Are not located in their design positions.
(3) Overall length measured at contact surfaces is reduced more than 3/16 inch.
(4) Have bottom surfaces which are uneven to the extent of 1/64 inch as determined
by a straight edge.
(5) Are flat on top per the following table:
Nominal Journal Size
Wear Limit Flat Lengthwise
4 1/4 x 8 inches
3 1/4 inches
5 x9 inches
5 1/2x 10 inches
4 1/2 inches
6 x11 inches
6 1/2 x 12 inches
5 1/2 inches
d. Defective plain bearing box. Plain bearing boxes are defective and shall be repaired
or replaced as needed if they :
(1) Do not maintain free oil.
(2) Have a box lid that is missing, broken, or open except to receive servicing.