TM 9--2350--292--20--2
0720 00--5
TORQUE LIMITS -- CONTINUED
0720 00
FASTENER GRADE
In addition to being classified by thread type, threaded fasteners are also classified by material. The most familiar
fastener classification system is the SAE grading system (Table 5).
Table 5. SAE Screw and Bolt Markings
SCREWS
BOLTS
SAE GRADE 2
NO MARKING
SAE GRADE 6
4 RADIAL DASHES
90 APART
SAE GRADE 3
2 RADIAL DASHES
180 APART
SAE GRADE 7
5 RADIAL DASHES
72 APART
SAE GRADE 5
3 RADIAL DASHES
120 APART
SAE GRADE 8
6 RADIAL DASHES
60 APART
Markings On Hex Locknuts
GRADE A -- No Marks
GRADE B -- 3 Marks
GRADE C -- 6 Marks
GRADE A -- No Notches
GRADE B -- One Notch
GRADE C -- Two Notches
GRADE A -- No Mark
GRADE B -- Letter B
GRADE C -- Letter C
TORQUE LIMITS FOR ENGINE
The following tables list lubricants and torques for fasteners used on the AVDS--1790--8CR Engine.
HOW TO USE TORQUE TABLES
a. Measure the diameter of the screw, stud, nut, or pipe plug you are installing.
b. Use the appropriate table for nuts and bolts (Table 6), pipe plugs (Table 7) or studs (Table 8).
c. Under the heading SIZE, look down the left hand column until you find the diameter of the screw, stud, nut or pipe
plug you are installing, then read across the table to find the proper torque.