SEAL 2720759 - Caterpillar

Clean the crankcase breather regularly in order to prevent excessive crankcase pressure that will damage the engine's seals.Perform this maintenance when the engine is stopped.The cleaning procedure depends on the type of crankcase breather.Canisters
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Crankcase breather (canister) (1) Wing nuts
Remove wing nuts (1) and the covers.
Remove the elements and discard the elements.
Clean the inside of the breathers' bodies and the covers. Inspect the covers' gaskets for good condition.
Install new elements.
Install the covers with wing nuts (1) .Breather Assemblies
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(1) Clamp (2) Tube (3) Clamp
Loosen clamp (1). Slide the clamp down tube (2) .
Loosen clamps (3). Remove both breathers as a unit.
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(4) O-ring seal
Remove O-ring seals (4) from the valve covers. Inspect the O-ring seals for good condition. Obtain new O-ring seals, if necessary.
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(5) Breather assembly (6) Clamp (7) Hose tee
Remove two clamps (6). Remove both breather assemblies (5) from hose tee (7) .Inspect the hose tee for cracks. If the tee is cracked, discard the old tee and obtain a new tee for installation.
Turn the breathers upside-down in order to inspect the condition of the breather elements.Clean the breather elements with clean, nonflammable solvent. If the breather elements remain contaminated after the cleaning, discard the breather assemblies and obtain new breather assemblies. Do not attempt to disassemble the breather assemblies.Allow the breather elements to dry before installation.Note: Coat the rubber parts with clean engine oil or petroleum jelly in order to make installation easier.
Place clamps (6) over the parts of hose tee (7) that will receive breather assemblies (5). Install the breather assemblies into the tee. Tighten the clamps to the torque that is listed in the Service Manual, "Specifications".
Coat O-ring seals (4) with clean engine oil. Place the O-ring seals on the valve covers.
Place clamps (3) around the parts of the breather assemblies that will be attached to the valve covers. Install both breather assemblies as a unit. Tighten the clamps.
Place clamp (1) on the part of the hose tee that will receive tube (2). Install the tube into the hose tee. Tighten the clamp to the torque that is listed in the Service Manual, "Specifications".