ENGINE AR-COMPLETE 1299752 - Caterpillar

Cleanliness
Whenever work is performed on any hydraulic system, it must be kept in mind that the hydraulic motors, pumps and valves are finely machined, close tolerance mechanisms that can tolerate very little, if any, dirt. The filters in the systems will keep the hydraulic oil clean during normal operation, but dirt that gets into the system during repair work is normally downstream from the filters. This dirt can lodge in a pump, motor or valve and cause immediate failure, or it can start a wearing process that releases other contamination in the system and leads to a failure later. KEEP IT CLEAN - DIRT KILLS HYDRAULIC SYSTEMS.The portion of the machine to be worked on should be cleaned with a steam cleaner, solvent or detergent before opening the hydraulic system. If a steam cleaner or water is used, precautions must be taken to prevent water from entering the hydraulic system or shorting out electrical components.The work area must be kept as clean as possible. Working on a hydraulic system in the open to save time is a gamble that should be carefully considered before starting. When it is necessary to work on a system in the open, provide as much protection for the system as possible.Before a component is removed, caps and plugs should be available to immediately cover all openings. Components that are removed should be placed in plastic bags until they are to be worked on or reinstalled.Clean nonflammable solvent should be used to clean all metal parts before installing them in a component or in the system. However, seals and gaskets should never be cleaned in solvents. The solvents may attack the material in the seal or gasket, causing it to break down in the system, and lead to contamination.Assembly Hints
Care should be exercised in assembling components and lines. Rough handling or careless assembly can cause gouging or chipping of metal parts and release metal chips in the system. The gouges and chips can in turn cause the surfaces of mating parts to chip or wear off, releasing more metal chips.Over tightening line connections can also lead to contamination from metal chips or from scuffed seals, as well as causing leaking connections. Tighten connections only until they are snug. If excessive force is required to stop a leaking connection, find the reason and replace parts of the connection as necessary.