Robinson R66 - Preparing Engine for Rolls-Royce Maintenance Facility

71-11 Preparing Engine for Rolls-Royce Maintenance Facility
NOTE
Cap and plug Rolls-Royce engine model 250-C300/A1 engine
fluid ports, electrical connectors, etc., and in removed
components, progressively during procedure to prevent foreign
object contamination.
1. Refer to Figures 71-1 and 71-2. Remove hardware securing MS21919WCH clamp(s) to
engine vertical firewall and F577-5 bracket (earlier R66s). Loosen B277 clamp(s) and
remove A729-68 tubes (if installed), breather hose/tube, and F170 fitting. Install plug.
2. Refer to Figure 76-1. Remove D930-2 spring from fuel control unit.
3. Refer to Figure 71-4. Remove hardware securing F169-2 base (and F577-5 bracket, if
installed) to exhaust collector. Remove base (and bracket) and install exhaust collector
cover.
4. To remove (engine) electrical harness:
a. Disconnect engine harness’s plug from engine magnetic plug on bottom of engine
accessory gearbox.
b. Remove hardware securing harness wire terminal to igniton exiter box stud.
c. Cut and discard ty-raps as required, and disconnect G426-1 (fuel differential
pressure) switch assembly wire from harness at connectors. Cut and discard
stand-off ty-raps at switch wire and F741-1 line assembly.
d. Remove hardware securing (2) MS21919WCH4 clamps to (bottom of) engine gearbox.
e. Disconnect harness plugs from anti-ice valve assembly solenoid, anti-ice pressure
switch assembly, and N
1
speed pick-up assembly.
f. Remove hardware securing (2) MS21919WCH4 clamps to (2) engine-supplied
MS9592-050 brackets.
g. Remove hardware securing harness wire terminals to measured gas temperature
(MGT) thermocouple studs.
h. Disconnect harness plug from engine magnetic plug near oil line unions.
i. Cut and discard ty-raps as required, and disconnect D745-3 pressure switch
assembly from harness at connectors.
j. Remove hardware securing F577-1 and F577-3 bracket assemblies to (right side
of) engine gearbox. Remove harness.
5. Remove engine inlet bellmouth per § 71-23 Part A steps 2 and 3.
JUL 2020 Chapter 71 Powerplant Page 71.7