BREATHER AS 2784694 - Caterpillar

The term "fluid conductors" as used in this Article includes, but is not necessarily restricted to, all hoses, tubes, pipes, lines, stems, fittings, couplings, connectors, unions, etc. through which a fluid is transmitted.
Over the years improvements to hoses and tubes have increased their service life significantly. Nevertheless, these areas of the machines should not be overlooked during preventive maintenance.
We urge all dealers to work closely with users and give them information regarding inspections of machines for correctly installed hoses and tubes. This applies to all applications of the various systems-hydraulic, power train, fuel, coolant, etc. The items to look for are listed in this Article, and most of these items are in the Operation and/or Maintenance Guides under the "Safety" topic.
Maintenance Items
Do not bend or strike high pressure fluid conductors with a hammer or other tools. Do not install bent or damaged fluid conductors.
Do not touch hot fluid conductors with bare hands or arms. Burns can result.
Do not twist hoses during installation. If one end of a hose with any type of a stem except a straight stem is tightened, it is possible to twist the hose while attempting to connect the other end. It is a good idea to first connect each end loosely, then properly orient the hose assembly, and then tighten the connections.
Repair or replace any loose or damaged fuel, oil or coolant fluid conductors. A leak (coolants included) can contribute to a fire.
Check lines, tubes and hoses thoroughly. Use a piece of sheetmetal or cardboard to check for leaks. Do NOT use your bare hand. Tighten all connections to the recommended torque (do NOT overtighten).
Replace a line, tube or hose with a new part of the correct size and strength rating if any of the following conditions are found. See illustration.
... (A) End fittings damaged, bent or misaligned.... (B) Armor protection has become embedded in the outer cover.... (C) Evidence of kinking or crushing of the flexible part of the hose.... (D) Outer covering has a spot that has ballooned outward.... (E) Outer covering chafed or cut, and wire reinforcing exposed.... (F) End fittings damaged or leaking.... (G) Hoses damaged, leaking or weeping.
Specific items to look for on lines, tubes or hoses.Be sure that all clamps, tiedowns, guards and heat shields are installed correctly to prevent vibration, rubbing against other parts, and excessive heating from hot engine parts during operation. Reposition hoses and/or tubes as necessary to avoid contact with any nearby parts.
Most reported hose or tube failure incidents from the field are a result of contact with other machine parts caused by improper reassembly, which did not allow for any movement during machine operation, or the failure to replace tiedowns or clamps around hoses or tubes. This causes abrasion-type wear and a failure occurs. If atomized spray contacts a hot part, this could result in combustion.
Operational Items
Caterpillar recommends that all machine operators make a " Walk Around Inspection" before starting the engine, and at each shift change. Operators should be reminded to inspect