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TM 10-3930-669-20
E-4. TORQUE INSTRUCTIONS.
Preloading is applied with a torque wrench that is calibrated in foot pounds (lb-ft) or newton meters (N•m). Preloading is
applied before angle torques. All angle torques listed in Table E-1 are accomplished by turning the screw/nut a specific
number of degrees from a zero reference point as shown. The tightening angle is obtained by turning the handle of the
wrench being used to the desired angle selected from a clock face you mentally superimpose over the screw head.
Torquing of two or more screws securing one assembly should be accomplished in an alternating fashion to ensure
assembly seating and equal load distribution. For example, if angle torque specified is 30° initial then 30° final, proceed
as follows:
a.
Coat screw and surface under screw head
with engine oil, MIL-L-2104.
b.
Set screws squarely to ensure assembly
seating.
c.
Apply specified preload with torque wrench.
d.
Using angle torque meter and socket
wrench, apply 30° initial torque to screw 1.
e.
Apply 30° initial torque to screw 2.
f.
Apply 30° final torque to screw 1.
g.
Apply 30° final torque to screw 2.
Table E-1. Torque Specifications
Preloading
Angle in Degrees or
Total
Torque Values
Application
Ib-ft
N•m
Stage 1
Stage 2
Stage 3
Stage 4
Degree
lb-ft
N•m
Cylinder head
29.5
40
45°
45°
45°
30
165°
-
-
Cylinder head screw
-
-
-
-
-
-
-
59-66
80-90
plug
Rocker arm bracket
-
-
-
-
-
-
-
21
28
nut
Rocker chamber
-
-
-
-
-
-
-
7
10
cover screw
-
(+4; 2)
(+5; 3)
E-2
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