DRESSTA TD-25M EXTRA, Service Manual

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TRACKS OR WHEELS
SECTION 15
Page 3
DRESSTA TD-25M EXTRA
TRACK CHAIN
Checking Track Tension
Place a wooden block approximately 300 [mm] in height, under the foremost track shoe lug. Drive
the machine forward until the track chain is tight along the ground and around the sprocket. Apply
and lock the brake; stop the engine. Stand on the track between the front idler and the first track
idler to accumulate all the chain slack at this point. Place a straightedge on the track so the ends
rest over the front idler and track idler. With a ruler, measure the clearance between the bottom
of the straightedge and the top of the shoe grouser at the midway point between the idlers. If this
clearance is not to specifications adjust track tension according to specifications in Paragraph 2.
Adjusting Track Tension (Refer to Fig. 15.1)
Track chains are adjusted by hydraulic pressure. Lubricant is introduced into the hydraulic cylinder
(which is attached to the front end of the track spring housing) by the use of a lubrication fitting (2).
This lubricant, acting upon the piston within the hydraulic cylinder, forces the front idler fork and
front idler forward for track adjustment. The relief valve port (1) is used to relieve the hydraulic
pressure.
Fig. 15.1. Track Adjuster
1. Relief Valve 2. Lubrication Fitting (Ball Check Valve)
DANGER! To avoid possible injury, always stand to the side of the relief valve
and fitting when making track adjustment. The pressure in the front idler fork is
held by the relieve and ball check valves. A loose or improper thread fit of either
of these parts can allow them to be ejected by the pressure of lubricant, causing
possible injury. When relieving track tension, never loosen these valves more
than 2 – 2 ½ turns.
If adjustment becomes necessary, remove the bolts securing the track adjuster cover to the track
frame and proceed as follows: