ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
5
MM-11-21
Nov
5/13
(3)
Belt Rib Surface
Rib cracking is a normal occurrence on the belt and is caused primarily by the
reverse bend idler. The cracks normally extend to the base of the rib and go
no further. Numerous cracks of this type are not significant. The belt should be
examined for cracks which have extended below the base of the ribs and, if
this has occurred, the belt should be removed. This is very important if the
cracks extend to the cord line and the cord is exposed when the crack is
opened.
Loss of small pieces of rib section may accompany the rib cracking. This is
normally a random occurrence. The belt should be replaced if there is a loss
of three or more adjacent ribs for a length of two inches or more. The belt
should be replaced if there is any piece of rib missing which is of sufficient
depth to leave the cord exposed.
NOTE:
Do not reverse belt to perform this inspection. Unnecessary
damage may result.
(4)
The belt should be replaced:
(a)
Whenever it has been determined that cord failure exists.
(b)
Whenever edge damage goes beyond the first “V” groove.
(c)
When missing pieces of the “V” area become large enough to cause
vibration in the drive system.
(5)
Reference:
Photographs A, B and C are examples of serviceable belts (see
Figure 11-7).
Reference:
Photographs D, E and F are examples of unserviceable belts
which should be replaced (see Figure 11-7).
E. Drive Belt – Installation
(1)
Slide the belt between the drive shaft and forward coupling half and ease belt
on top of the upper pulley.
(2)
Pivot rear actuator arm back into position and install mounting hardware.
(3)
Install nut and cotter pin on inboard bolt of actuator arm.
(4)
Torque and safety wire outboard bolts to yoke.
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