ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
7
MM-2-16
Aug
22/16
2-16. Torque Data
Unless specified in Table 2-4 and/or in this manual’s maintenance procedures or as called
out in the component manufacturer’s specifications, all hardware should be torqued to
standard torque values listed in Tables 2-5 through 2-12.
Table 2-4. Special Torque Values
Location Torque
Value
1.
Main rotor mast nut
400 ft-lbs/542.3 Nm
2.
Main rotor transmission pinion nut
250 ft-lbs/339 Nm
3.
Main rotor blade attachment nuts
50 ft-lbs/68.2 Nm
4.
Main rotor blade drag link nuts
140 in-lbs/15.9 Nm
5.
Main rotor damper pivot nut
190 in-lbs/21.6 Nm
6.
Main rotor hub U-block lower nut
50 ft-lbs/67.8 Nm
7.
Main rotor hub U-block upper nut
20 ft-lbs/27.1 Nm
8.
Upper swashplate guidetube nuts
240 in-lbs/27.1 Nm
9.
Engine mount nut
460-500 in-lbs/52-56.5 Nm
10.
Tailcone attachment bolts
240 in-lbs/27.3 Nm
11.
Tail rotor assembly retention bolt
300 in-lbs/34.1 Nm
12.
Tail rotor blade grip nuts
1
75 in-lbs/8.5 Nm
13.
Lower engine pulley to crankshaft bolts
50 ft-lbs/67.8 Nm
14.
Pitch change bellcranks
a. Push/pull rod bolt
b. Push/pull rod bolt with floating bushing
40 in-lbs/4.5 Nm
75 in-lbs/8.5Nm
15.
Landing gear pivot points (all)
40-60 in-lbs/4.5-6.8 Nm
16.
Landing gear oleo pivots points (all)
40-60 in-lbs/4.5-6.8 Nm
17.
Tail rotor driveshaft taper pins
25 in-lbs/2.8 Nm
18.
Dogleg to push/pull rod nut
130-140 in-lbs/14.7-15.9 Nm
19.
Dogleg to swashplate nut
40-60 in-lbs/4.5-6.8 Nm
20.
Idler yoke/shaft jam nut
40-45 in-lbs/4.5-5.1 Nm
21.
Fuel pump and fuel injector attach nuts
204 in-lbs/23.1 Nm
1 Foot-Pound (ft-lb) = 1.3558 Newton Meter (Nm)
1 Nm = 0.7376 ft-lb
1
Torque for oversize bolts: 140 in-lbs/15.9 Nm maximum.
UNCONTROLLED COPY WHEN DOWNLOADED OR PRINTED
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