BURNISHING TRACK CLUTCH & BRAKE FACINGS TO IMPROVE PERFORMANCE
The facing material on the two electric track clutches and on the two electric track brake assemblies can
become glazed from operation so that excessive slippage occurs. Poor clutch operation will result in both R.H.
& L.H. drives slipping, or in one track consistently failing to keep up with the other so that an abnormal amount
of steering is required to maintain a straight course.
Poor brake operation will result in an inability to hold position on uphill paving run.
When poor performance of a clutch or brake is suspected, the unit in question should first be 'checked for
armature "hang-up" on the drive pins, oil on the friction faces, improper electrical function, or worn-out friction
faces. (See details of dimension checking in preceding paragraphs.) Slippage can also be due to an overload
condition. The drive train and tracks should be inspected for mechanical binding.
If none of the above factors seem to be the cause of clutch slippage, the performance of the clutches may
be improved by carrying out a burnishing operation to remove "glaze" from the friction surfaces. (The same
effect cannot be obtained by using a solvent, as during an oil removal effort, nor by "roughing-up" the friction
surfaces by hand!)
Burnishing Track Clutches
(1) Move paver to where center of main frame front edge is in direct contact-with a suitable immovable
object, which can safely withstand the full force of paver drive power. IMPORTANT! Be sure that no truck hook
or other part of the paver will make contact and be damaged by the full force of the paver drive. The tracks
should be resting on hard dry soil or other dry surface which will not break-up or be badly damaged by the full
force of the paver drive.
(2) When paver is in place, arrange electric system so that brakes will be on when the Track switches are
at the Travel position. (For early model paver brakes the brake coil must be energized. For pavers with
electrically released brakes the coil must be de-energized.)
(3) Arrange track speed controls for high speed travel.
(4) Move the track switches to the center position (neutral).
(5) Move throttle switch to Full position.
(6) Intermittently move one track switch to Travel position then back to neutral so that the clutch is
momentarily engaged and the clutch surfaces heat-up rapidly to above their normal operating temperature.
(150 F - approx.).
IMPORTANT! The clutch should not smoke from intense heating.
Repeat this procedure on the opposite track. After both clutches have reached the elevated temperature
continue the procedure for at least five minutes at a slower rate so that the temperature is maintained but not
exceeded. Both clutches are then burnished at the same time by alternate switch actuation.
Burnishing Track Brakes
(1) Arrange track speed controls for high speed travel.
(2) With track switches at Brake position, move throttle switch to Full position. When engine is warmed up
for operation move both track switches to Travel and when paver has attained its maximum forward speed,
move one track switch to Brake then back to Travel as quickly as possible. When this is done fast enough, the
brake does not "grab", but
does make sufficient contact to the heat surfaces.
Caution! The operator should however, be braced for sudden deceleration.
Repeat this procedure until the brake is hotter than during normal operation (I 500 to 2000 F) but not
smoking. Then repeat the same burnishing effort on the opposite brake.
(NOTE: If this procedure presents a problem, the same effect can be obtained by blocking-up the paver
so that both tracks are completely off the ground, and there is no actual paver movement).
(3) When the brakes have cooled completely, test paver steering to see that normal operation of the
brakes has been restored.