GILLIG LOW FLOOR, Service Manual, Page: 104 / 506

Engine
04
OK
20-100-x150
BASE
CRACKING
Figure 3-19, Base Cracking
OK
20-100-x147
FABRIC RUPTURE
Figure 3-20, Fabric Rupture
OK
20-100-x151
COVER
TEAR
Figure 3-21, Cover Tear
DRIVE BELTS
Proper care and maintenance of drive belts is an important part of good engine maintenance. Proper belt
tension and the condition of the pulley grooves are most important.
Since belts and pulleys wear with use, look at all frictional surface areas for signs of wear. Normal wear
can be recognized as even wear, both on the belt and the grooves of the pulley. It is the unusual signs of
wear that indicate a problem. When checking, remember that belt failures may have been caused by a
bad pulley, a misaligned drive, or by some other faulty mechanical component.
Troubleshooting Belt Problems
Base Cracking
(See Figure 3- 19 .) Excessive cross checking extending into the
rubber on the base of a belt that shows little or no side wear indi-
cates that the belt has been operated under incorrect tensioning, has
been slipping, or is worn out due to excess use. In any case, the belt
must be replaced and re-tensioned. This does not indicate any defect
caused during manufacturing.
Belts may fail after three (3) or four (4) seasons of use due to fatigue.
Small cracks in the cover material of a belt are not an indication of
belt failure. However, if the base of the belt also shows cross check-
ing, the belt has been exposed to weather to the extent that the inner
fabric is beginning to rot and should be replaced.
Fabric Rupture
(See Figure 3- 20.) A fabric rupture can be caused by operating a belt
over a badly worn pulley; by too much tension, which forces the belt
down into the groove; or by foreign objects falling into the pulley
groove.
Cover Tear
(See Figure 3- 21.) A tear in the cover of a belt is normally a result
of the belt accidentally coming into contact with some part of the
coach. It is no fault of the belt or its construction. Cover tears are
usually caused by belts running too loosely, which allows them to
be “thrown out” centrifugally and rub on other components of the
vehicle. Proper belt tension will prevent this failure.
A slight raveling of the belt covering at the splice
location does not indicate imminent belt failure.
Simply cut off the loose raveling.