HOUSING AS 8D7694 - Caterpillar

Overhaul Information
An overhaul is replacing the major worn components of the engine. An overhaul interval is a maintenance interval that is planned. The engine is rebuilt with certain rebuilt parts or new parts that replace the worn parts.An overhaul also includes the following maintenance:
Inspection of all the parts that are visible during the disassembly
Replacement of the seals and gaskets that are removed
Cleaning of the internal passages of the engine and the engine blockMost owners will save money by overhauling the engine at the intervals that are recommended in this Operation and Maintenance Manual. Consider the graph in Illustration 1.
Illustration 1 g00745964
(Y) Cost
(X) Time
(1) Cost of maintenance and repair that is planned
(2) Cost of maintenance and repair that is not plannedIn Illustration 1, line (1) represents the maintenance and repair costs for an owner that followed the recommendations for inspection, maintenance, and repair. The peaks represent overhauls.Line (2) represents the maintenance and repair costs for an owner that chose to operate beyond the recommended intervals. The initial cost of the “repair-after-failure” philosophy is lower. Also, the first overhaul was delayed. However, the peaks are higher than the peaks for the customer that used the “repair-before-failure” philosophy .The higher peaks result from two key factors:
Delaying an overhaul until a breakdown increases the chance of a catastrophic failure. This type of failure requires more parts, labor, and cleanup.
Excessive wear means that fewer components will be reusable. More labor may be required for salvage or repair of the components.When all the costs are considered, “repair-before-failure” is the least expensive alternative for most components and engines.Waiting until the engine exhibits symptoms of excessive wear or failure is not practical. Waiting is not less costly. A planned overhaul before failure may be the best value for the following reasons:
Costly unplanned downtime can be avoided.
Many original parts can be reused according to the guidelines for reusable parts.
The service life of the engine can be extended without the risk of a major catastrophe due to engine failure.
Achieve the best cost/value relationship per hour of extended service life.Overhaul Inspection
Refer to the Service Manual for the disassembly and assembly procedures that are necessary to perform the required maintenance on the items that are listed. Consult your Cat dealer for assistance.To determine the reusability publications that are needed to inspect the engine, refer to Guidelines for Reusable Parts and Salvage Operations, SEBF8029, "Index of Publications on Reusability or Salvage of Used Parts".The Guidelines For Reusable Parts and Salvage Operations is part of an established Cat parts reusability program. These guidelines were developed to assist Cat dealers and customers reduce costs by avoiding unnecessary expenditures for new parts. If the engine parts comply with the established inspection specifications, the parts can be reused.The use of out-of-spec parts could result in unscheduled downtime and/or costly repairs. The use of out-of-spec parts can also contribute to increased fuel consumption and reduction of engine efficiency. New parts are not necessary if the old parts can be reused, repaired, or salvaged. Otherwise, the old parts