HEAD 8M0200 - Caterpillar

Track Roller Frames
Illustration 1 g03892081
(1) Front idlers (2) Front track roller frame (3) Access panel (4) Track carrier roller (5) Hard bar (6) Pivot shaft (7) Rear track roller frame (8) Rear idlersThe two track roller frames are mirror images of each other. A front idler (1), rear idler (8), and a track carrier roller (4) are fastened to each track roller frame. Access panels (3) for the recoil cylinder and the mechanism for track adjustment are located between the pivot shaft and the hard bar.
Illustration 2 g03892112
(9) Track adjusting cylinder (10) Front track roller frame recoil group (11) Fill valve (12) Relief valveEach track roller frame has a track adjusting cylinder (9) that is filled with multipurpose grease or oil. When grease or oil is added through grease fill valve (11), the pressure pushes the track adjusting piston forward. The forward movement of the track adjusting piston tightens the track.In order to loosen the track, loosen grease relief valve (12). This releases grease or oil from the chamber in the track adjusting cylinder. When the grease or oil is allowed out of the chamber, the reduction in pressure allows the track adjusting piston to move to the rear which releases the tension on the track. Grease relief valve (12) can be accessed through access panel (3) .The following events will occur when foreign material gets between the track and the other parts of the undercarriage:
The front idler and the track adjusting piston move toward the rear of the machine.
Since the grease or oil in track adjusting cylinder (9) cannot be compressed, the spring of recoil group (10) is compressed.
The compression of the spring allows the debris to pass between the track and the other parts of the undercarriage without stretching the track. When the foreign material has passed through the undercarriage, recoil group (10) returns to the forward position.