DRESSTA TD-25M EXTRA, Service Manual

Page: 553 / 595

TRACKS OR WHEELS
SECTION 15
Page 7
DRESSTA TD-25M EXTRA
TRACK CHAIN
Oil leakage noted at joint area, very difficult on units operating in field. Hand feel for warm or hot
bushings after machine has been running. Check for extending chain pitch. Squeaking while going
around front idler or sprocket. When it has been determined which joint is leaking, joint should
be identified for repair. One method of identification is to spray paint squeaking joint.
NOTE: Two methods of repairing a track are available. One method is to repair complete chain
using a twin-head hydraulic track table press. Another method is to rebuild only leaking chain joints
using a portable 100 or 150 [ton] track press (Refer to SERVICE / SPECIAL TOOLS).
COMPLETE CHAIN REBUILD
Disassembly
1. Using a slow-speed drill and a 12 [mm] drill bit, remove rubber plugs (10, Fig. 15.5) from pins
(4). Position track chain on track press so that bushing end (non-threaded end) of split link (8
and 9) is toward rams. Remove track shoes.
2. Install disassembly adapters on ram heads. Advance track and tower table so split link drops
into saddle. Press pin out of left link (8), then press pin out of right (9) link. Remove loose split
links from press.
3. Advance track so next link drops into saddle. Press pin (4) and bushing (3) out of right link (6),
then press pin and bushing out of left link (7). Remove loose links, bushing and pin from press.
4. Repeat step 3. with remaining sections of chain. Remove seals (11) from track links. Inspect
parts for wear/damage or improper assembly. Discard any parts which would adversely affect
rebuild.
3. Tag all mating parts to if need be installation.
Reassembly
1. Dress up parts with emery cloth as required. Clean parts. On new or reused pins, mark an index
mark (1, Fig. 15.6) on lube hole end (2) of pins on opposite side of cross-drilled hole (3).
2. Install assembly adapters on ram heads. Bolt halves of split links together and position them on
press assembly adapters. Position a bushing in press saddle. Press links onto bushing until
bushing is seated against assembly adapter. Remove bolts securing two halves together.
Advance track on press and position a pin in assembled bushing. Apply a coat of oil on ends of
bushing with tissue (not your fingers) as shown in Fig. 15.8, being careful not to get it on pin
surface. Position next bushing in press saddle. Check that seal halves are properly assembled
as shown in Fig. 15.7.
3. Install O-rings (2, Fig. 15.7) and seals (1) and thrust rings (7) in counterbore of next chain links
(6 and 7, Fig.15.5) and apply LOCTITE #680 sparingly in outer half of pin bore of links (6 and 7)
as shown in Fig. 15.9. Position links on press assembly adapter. Check that index mark (1,
Fig.15.6) is at bottom. Lube holes (2) must all face in same direction.
4. Press links (6 and 7, Fig.15.5) onto pins (4) and bushings (3) being sure that link counterbore
and bushing face are seated against thrust ring (5). Do not exceed force indicated as this can
damage ring (5). Do not adjust links for bolt hole location. Before chain is moved to next
position, pressurize joint with 350 [kPa] of air pressure. After pressure holds for 10 [sec], place a
special purpose rubber plug in end of pin of assembled joint using mounting tool (refer to
SERVICE/SPECIAL TOOLS).Tap it in until it is flush or slightly below chamber of pin hole.
5. For final check of each seal use seal tester or vacuum pump (refer to SERVICE/ SPECIAL TOOLS).
Insert lubricator nozzle of tool through plug. Pull a vacuum of 70 ± 5 [kPa] and hold for 10 [sec]. In
event that vacuum cannot by held, either seal to bushing face or chain pin to link bore mating
surfaces are leaking. To determine which side is leaking, pressurize joint with 350 [kPa] of air
pressure, apply soap solution to both seal areas and check for soap bubbles. After finding which side
is leaking, joint must be rebuilt. If vacuum holds for 10 [sec], fill evacuated pin with oil under 100 to
170 [kPa] to obtain required oil level 54 to 74 [mm] below the end face of the pin.