Owners manual

TORQUING BOLTS
As a rule, when a bolt is installed, the nut (over a washer) should be turned and not the bolt's head. Unless
a torque wrench is used the tendency is to undertighten large bolts and overtighten small ones. Suggested
torques are given below. These suggestions do not apply if the bolt or nut has been specially lubricated.
Bolts should not be Installed or Torqued more then one time.
Replace any used bolts with the exact same size and grade.
The SAE has established a sequence of grades from 0 to 8 for steel bolts, on the basis of
the metal from which the bolt is made and the manner of manufacture. Available grades
run from 2 to 8, with 8 the strongest. Higher-grade numbers almost always mean
increased strength (an exception is that some grade 6 bolts are stronger than grade 7).
The heads of steel bolts are marked to identify their grade.
SAE STANDARDS FOR STEEL BOLTS
IDENTIFYING BOLT GRADE
0,1&2 3 5
678
BOLT GRADES
& TORQUING INFORMATION
BOLT DIAMETER IN INCHES
¼" ½" ¾"5/16" 3/8" 7/16" 9/16" 5/8" 7/8" 1”
SAE 2
SAE 3
SAE 5
SAE 6, SAE 7
SAE 8
4.6 9 15 24 36 50 69 117 184 273
6.9 14 24 38 57 82 113 198 317 477
7.5 15 25 40 59 83 114 196 309 459
9.7 19 34 55 83 120 166 291 469 710
10.5 21 37 60 90 130 180 316 509 769
12.7 25 45 72 109 157 217 381 615 929
BOLT GRADE
SOCKET HEAD
CAP SCREWS
Approximate Torque Settings for Cadmium-plated Bolts, specially lubricated, in foot-pounds.
All Grading on Hex Head steel bolts can easily be identified. Grading is identified by the number of lines
on the head of each bolt (Please refer to the illustrations below).