MAINTENANCE OF THE M88A1 - OD1672 - LESSON 1/TASK 2
Roadwheels (5) (figure 4, view A, on the previous page). Six pairs of
forged aluminum or steel roadwheels are individually mounted on six hubs on
each side of the vehicle. They provide the means for the vehicle to move as
they roll on the upper surface of each lower track span.
includes a solid rubber tire bonded to its outer flanged surface. The solid
rubber tire absorbs the shock as the vehicle moves along the ground.
also serves to quiet the interaction between the roadwheel and track. There
is a space between the dual wheels, providing a channel in which the track
center guides travel and protects the wheels against damage from the steel
center guides. The center guides align the track and serve to keep it on
the suspension system.
Compensating Idler Wheels and Track Adjusting Links. Two compensating
idler wheels (6) are bolted to a single hub on each side and in front of the
The space between the dual mounted wheels provides the
track aligning channel for the center guide.
The hub is roller bearing
supported on the lower spindle of the compensating idler arm. The arm upper
spindle is sleeve bearing mounted into an internally machined cavity in the
front forward corners of the vehicle hull.
The compensating wheels are
connected to the front roadwheels by track adjusting links (9).
front wheel support arm is displaced from its normal vehicle loaded position
by an obstruction or depression under the track, the compensating idler
wheels are moved forward or rearward taking up the slack to maintain
constant tension on the unloaded free portion of the track. The adjusting
link assembly may be lengthened or shortened to adjust the amount of track
tension. Track tension is set and maintained by this screw-type adjusting
link which is connected between the number 1 roadwheel arm and the
compensating idler arm on both sides of the vehicle.
Roadwheel Arm Assembly. The roadwheel arm assembly at each roadwheel
position consists of a machined spindle fitted into a forged steel arm. An
eye fitting, welded to the positions 1, 2, and 6 arms, provides the lower
attaching point for the direct action shock absorbers used at these
positions. The single tapered lower spindle provides the alignment mounting
for the roadwheel hub inner and outer roller bearings.
A lower spindle
protrusion through the arm is the arm