Robinson Helicopter Company RTR 660, Maintenance Manual

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63-30 Rotor Brake
Refer to R66 Illustrated Parts Catalog (IPC) Figure 63-9.
A. Removal
1. Remove (engine-driven) F910-1 yoke assembly per Section 63-21, Part C steps 1 thru
3.
2. Refer to Figure 63-2. Detach D126-2 cable assembly from B112-3 spring. Detach
B774-3 spring from gearbox cartridge retaining screw or rotor brake assembly link.
3. Remove hardware securing D2VW-5-1MS switch to brake assembly link.
4. Remove hardware and spacers securing brake assembly mounting bars to gearbox
cartridge. Remove G033-1 brake assembly F256-1 shield (see Figure 63-1).
B. Installation
1. Refer to Figure 63-2. Verify minimum 0.030 inch rotor brake pad thickness on both arm
assemblies.
2. Verify F910-1 yoke assembly and pinion splines are clean and undamaged. Coat splines
of pinion with B270-21 protectant.
3. Install F256-1 shield, then position G033-1 brake assembly over pinion and install
spacers and hardware securing brake assembly mounting bars to gearbox cartridge.
Standard torque screws per Section 20-32 and torque stripe per Figure 5-1.
4. Install yoke on pinion shaft. Place a wood block between firewall and yoke flange (to
prevent yoke from rotating). Install pinion retaining nut and washer and special torque
nut per Section 20-33. Coat nut and exposed pinion splines with B270-21 protectant.
When dry, torque stripe per Figure 5-1.
5. Attach B774-3 spring to gearbox cartridge retaining screw and rotor brake assembly
link. Attach D126-2 cable assembly to B112-3 spring.
6. Install hardware securing D2VW-5-1MS switch to brake assembly link, but do not
tighten. Adjust switch to open and close when gap between B112-3 spring lower
retaining screw screw head and G110-1 arm assembly is 0.10-0.20 inch with brake
disengaged. Pivot switch about lower fastener as required and tighten fasteners to set
gap.
7. Install hardware securing A947-2 (forward) plate assembly to F910-1 yoke assembly,
and A947-2 (aft) plate assembly to F642-1 shaft weldment. Shim engine driveline per
Section 63-11. Standard torque nuts and palnuts per Section 20-32, and torque stripe
per Figure 5-1.
8. Install tailcone cowling assembly per Section 53-23. Install engine cowling assembly
per Section 53-21.
SEP 2012 R66 Maintenance Manual Chapter 63 Main Rotor Drive System
Page 63.11