
Inspection
2 – 4 brake drive plate
Measure the 2-4 brake drive plate facing thickness at 3
points and calculate the average value.
If the average value is less than the specified limit, the 2-4
brake drive plate must be replaced.
2 – 4 brake drive plate facing thickness:
Standard = 2.0 mm (0.079 in)
Limit = 1.8 mm (0.071 in)
Low and reverse brake drive plate
Measure the low and reverse brake drive plate facing
thickness at 3 points and calculate the average value.
If the average value is less than the specified limit, the lo
and reverse drive plate must be replaced.
Low and reverse brake drive plate facing thickness:
Standard = 2.0 mm (0.079 in)
Limit = 1.8 mm (0.071 in)
2 – 4 brake return spring
• Check the number of effective 2-4 brake return spring
coils.
Effective return spring coils (Standard): 10.2
• Measure the 2-4 brake return spring outside diameter,
free length, and linear diameter.
If any of the measur ed values exceed the spec ified lim it,
the 2-4 brake return spring must be replaced.
2 – 4 brake return spring measurements (Standard):
Outside diameter = 6.9 mm (0.272 in)
Free length = 22.5 mm (0.886 in)
Linear diameter = 1.1 mm (0.043 in)
Low and reverse brake return spring
• Check the number of effective low and reverse brake
return spring coils.
Effective return spring coils (standard): 4.8
• Measur e the low and reverse br ake return spr ing outside
diameter, free length, and linear diameter.
If any of the measur ed values exceed the spec ified lim it,
the low and reverse return spring must be replaced.
Low and reverse brake return spring measurements
(Standard):
Outside diameter = 11.2 mm (0.441 in)
Free length = 22.3 mm (0.878 in)
Linear diameter = 1.1 mm (0.043 in)