ENGINE AR 4593881 - Caterpillar

Illustration 1 g00463967
Track link assembly that is used on machines with the STD undercarriage is shown. (1) Link (2) Bushing (3) Hole (4) Link (5) Retaining ring (6) Stopper (rubber) (7) Plug (polyurethane) (8) Ring (thrust) (9) Seal assembly (10) Pin (11) Link (12) LinkThe machine has a sealed and lubricated track with positive pin retention.Each of track links (1) and (4) fits over the preceding track link. Link (1) fits over link (11) . Link (4) fits over link (12) . The connection of the track links makes the track assembly.Each link has a counterbore in the end. The counterbore makes a fit with the preceding link. Seal assemblies (9) are installed in the counterbores of the links. Each seal assembly has a load ring and a seal ring. The load ring pushes the seal ring against the end of bushing (2) and the link counterbore.The seal ring gives a positive seal between the bushing and the link counterbore. The edge of the seal ring is against the end of the bushing.Thrust rings (8) are installed on pin (10) . The thrust rings give a specific amount of compression to the seal assemblies. The thrust rings also control the end play (free movement) of the track joint. The arrangement of the seal assemblies and the thrust rings keeps foreign materials out of the track joint and oil in the track joint.Pin (10) has hole (3) which is nearly the full length of the pin. Hole (3) is drilled radially in the pin near the center of the pin. Radial hole (3) allows oil flow to the surface between pin (10) and bushing (2) and to the lip of the seal rings.The oil gives lubrication to the pin and the bushing. The oil also adds moisture to the lip of the seal ring. The lip of the seal ring must be kept moist in order to prevent wear.The oil is kept in the pin by stopper (6) and plug (7) . The oil is installed in the pin through a hole in the center of stopper (6) . When the chambers in the pin are filled, plug (7) is installed in stopper (6) .Retaining ring (5) at each end of pin (10) gives the pin positive retention. This positive pin retention eliminates internal end play. Rings (5) are not removed unless the pins are removed. The removal of the pins shears the rings. New rings must be installed at reassembly.
Illustration 2 g00463968
(13) Master shoe (14) Bolts (15) Master linkTwo-piece master links (15) and master shoe (13) are held together with bolts (14) .Each pin and bushing assembly is sealed. There is independent lubrication for each pin and bushing assembly. The seals and lubrication oil help to prevent internal wear on the track joint. The interval for replacing the track pins and bushings is longer because the wear will only exist