will have the letters "REF" in the alowance
number. This index is in ascending FSN se-
column. To locate the referenced item, locate the
quence followed by a list of reference numbers
FSN or reference number in the index. The
in ascending alpha-numeric sequence cross-
earliest figure and item number is the referenced
referenced to the illustration figure number and
item. Items authorized for use as required but
not for initial stockage are identified with an
(2) Second. Using the Repair Parts List-
asterisk in the allowance column.
ing, find the assembly group of the repair part
i. Illustation. This column is divided as fol-
and the illustration figure number and item num-
ber referenced in the Index of Federal Stock
(1) Figure number. Indicates the figure
Numbers and Reference Numbers.
number of the illustration on which the item is
6. Federal Supply Codes for Manufacturers
(2) Item number. Indicates the Callout
number used to reference the item in the illustra-
a. Repair parts mortality has been based on
1500 hours of operation per year.
b. Parts which require manufacture or as-
sembly at a category higher than that authorized
for installation will indicate in the source col-
umn the higher category.
c. The following publications pertain to the
welding machine and its components:
TM 5-3431-228-14 Operator, Organization-
al, DS, and (GS Mainte-
TM 5-3431-228-20P Organizational Mainte-
nance Repair Parts and
Special Tools List.
to Locate Repair Parts
a. When Federal stock number or reference
number is unknown:
(1) First. Using the table of contents, de-
termine the assembly group within which the
repair part belongs. This is necessary since illus-
trations are prepared for assembly groups, and
listings are divided into the same groups.
(2) Second. Find the illustration covering
the assembly group to which the repair part be-
(3) Third. Identify the repair part on the
illustration and note the illustration figure num-
ber and item number of the repair part.
(4) Fourth. Using the Repair Parts List-
ing, find the assembly group to which the repair
part belongs and locate the illustration figure
and item noted on the illustration.
b. When the Federal stock number or refer-
ence is known.
(1) F i r s t . Using the Index of Federal
Stock Numbers and Reference Numbers find the
pertinent Federal stock number or reference