Bolt Torque
Got a screw loose?? (my wife keeps tell me that I do..)
Max Torque (foot-pounds) for clean, dry threads
| Bolt size – Thread pitch | Grade 2 | Grade 5 | Grade 8 | Special Alloy |
|---|---|---|---|---|
| 1/4-20 | 6 | 10 | 12 | 14 |
| 1/4-28 | 7 | 12 | 15 | 17 |
| 5/16-18 | 13 | 20 | 24 | 29 |
| 5/16-24 | 14 | 22 | 27 | 35 |
| 3/8-16 | 23 | 36 | 44 | 58 |
| 3/8-24 | 26 | 40 | 48 | 69 |
| 7/16-14 | 37 | 52 | 63 | 98 |
| 7/16-20 | 41 | 57 | 70 | 110 |
| 1/2-13 | 57 | 80 | 98 | 145 |
| 1/2-20 | 64 | 90 | 110 | 160 |
| 9/16-12 | 82 | 120 | 145 | 200 |
| 9/16-18 | 91 | 135 | 165 | 220 |
| 5/8-11 | 111 | 165 | 210 | 280 |
| 5/8-18 | 128 | 200 | 245 | 310 |
| 3/4-10 | 200 | 285 | 335 | 490 |
| 3/4-16 | 223 | 315 | 370 | 530 |
| 7/8-9 | 315 | 430 | 500 | 760 |
| 7/8-14 | 340 | 470 | 550 | 800 |
| 1-8 | 400 | 650 | 760 | 1130 |
| 1-14 | 460 | 710 | 835 | 1210 |
Torque specs for GRD 214
1/3/02 7:00:42 AM PST From: alfg@sk.sympatico.ca (Ralph Goff)
I have a Chiltons Scout manual and they give a general guide for torque values for the various different sizes and grades of bolts and studs. Now I am assuming the KB has 3/8 studs in the manifold like my S has. The Scout guide recommends 18 to 20 foot pounds for grade 1 or 2 studs. For the higher grade 5 studs they recommend 31 to 35 pounds. If by chance you have grade 6 or 7 studs then the torque settings are 34 ft. lbs. These settings are for clean dry threads. If oil is used on the threads they advise to reduce the settings by 10%. Ralph in Sask.
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