in inaccurate tightening torque. Failure to follow these procedures could result in wheel
mounting failure and loss of vehicle control.
13. Install wheel and tire assembly. Tighten 9/16 lug nuts (rear) per Chapter 2.
Remove safety stand and lower tractor.
1.6 WHEEL CYLINDERS
Wheel cylinders are used to apply hydraulic force to the rear brake shoes. There is one
wheel cylinder on each rear axle end.
NOTE: If the wheel cylinder is leaking or has failed, it is better to install a new one rather
than repair the old one. The time and cost involved to recondition a cylinder is usually
greater than its replacement cost.
1.6.1 Removal
1. Remove brake drum. Refer to paragraph 1.5.1.
2. Back off brake adjusting bolts if necessary to get clearance between drum and
brake shoes.
3. Disconnect brake line at cylinder. Plug brake line or secure clean rag around open
brake line to keep brake fluid from contaminating brake linings and work area.
4. Remove brake return spring.
5. Remove securing wheel cylinder to brake. Spread brake shoes apart until ends of
shoes clear cylinder. Remove cylinder.
1.6.2 Disassembly
1. Remove rubber boots from wheel cylinders.
2. Apply low-pressure compressed air to cylinder inlet (if needed) and force pistons
and cups from cylinder bores. Remove spring.
3. If needed, remove bleeder screw from cylinder.
1.6.3 Cleaning and Inspection
1. Clean all parts and dry with compressed air.
2. Inspect boots for tears, holes, and deterioration. Replace if damaged.
NOTE: A hard, crystal-like substance sometimes forms a ring in cylinder bore near where
piston stops when brake is released.
3. Inspect pistons, cups, and cylinder bores for scratches, scoring, pitting and
corrosion.
AUGUST 31, 2008 CHAPTER 3 OVERHAUL
PAGE 10 1 GENERAL REPAIR
M140 Tow Tractor Manual No. 46054
To Next Page
Loading...
