TM 5-3820-239-15
Section X. TRACTION UNIT
(4) If the adjustment is not correct, or if
3-35. General
the unit drifts to one side or the other
The traction unit provides the propelling
while tramming, adjust the track by
motion for the unit. The only work authorized
loosening one of the adjusting screw
at organizational level is the checking and ad-
locknuts and tightening the other,
justment of the tracks, and tightening sprocket
using the track adjusting wrench.
stud nuts if required.
When the adjustment is correct,
tighten the locknut.
3-36. Servicing
b. Sprocket Stud Nuts.
a. Track Adjustment.
(1) Propel the pneumatic drill until the
Note. When the unit is new, it is extemely impor-
tant that the sprocket stud nuts be checked for
center of a grouser is directly over the
tightness after approximately 100 hours of operation
centerline of the rear wheel sprocket
After the initial check, annual rechecking is sufficient.
(2) Lay a straightedge across the track so
(1) Remove the dust shield and outer
that it rests on the grousers over both
support bracket (fig. 3-7) from each
the front and rear wheels.
traction unit rear sprocket.
(3) Check the dip at the midpoint be-
(2) Using a torque wrench, tighten the
tween wheels (fig. 3-13). The cor-
10 sprocket stud nuts to a torque of
rect adjustment is 2 inches from the
150 feet-pound.
bottom of the straightedge to the
(3) Install the outer support brackets and
top of the grouser.
dust shields.
