TURBOCHARGER GP 4712080 - Caterpillar

Illustration 1.A small paper Index book kept with the Bills of Material section of the Microfilm Library tells which fiche shows the Bill of Material for a specific special arrangement engine. Instructions for use are on the front of the Index.
The Bill of Material on a fiche is a microfilm copy of two or more pages of paper. The first frame shows a cover page of information. Important areas of this page are shown below.
At the upper left corner (Illustration 2) are the Bill of Material Number and the Change Number. Together they make the identification of a special arrangement engine as shown in Illustration 1. They form the number found on the serial number plate and in the paper index.
Illustration 2.
Illustration 3.In the upper right corner (Illustration 3) are shown the engine model number and the serial number range from which the special arrangement engine comes.
Illustration 4.In the chart on the lower part of the page (Illustration 4), column (1) shows the part numbers of the arrangements and groups from which the special arrangement was built. Column (2) shows their names. Columns (3) and (4) show the page numbers and parts books where illustrations and parts references for the groups can be found.
The modifications to the arrangements and groups start on the second frame (Illustration 5).
On this page, column (1) again shows the part numbers of the arrangements and the groups from which the special arrangement was built. Column (2) again shows their names. Column (3) shows the part number and column (5) shows the name of parts added to or canceled from standard parts groups. Column (4) shows whether the item was added (the + symbol) or canceled (the - symbol). Columns (6) and (7) show the part number and the name of the group or arrangement to which the change was made.
The Bill of Material can show part numbers of special groups for which Caterpillar does not have replacement service as a group. But another page of the Bill of Material will show the separate parts of the group and there is service for the separate parts.
The Bill of Material for a special arrangement engine shows all parts used to build the engine before shipment from Caterpillar. If other parts for which Caterpillar is not the source are added by the OEM, their replacement service must come from the OEM.
Illustration 5.