TORQUE LIMITS
TM 9-2815-225-34&P · Work Package 0053 00
SCOPE
This Work Package (WP) provides general torque limits for screws and fasteners used in this manual. Special torque limits are indicated in the maintenance procedures for applicable components and in table 4, Torque Specifications. The general torque limits given in this WP shall be used when specific torque limits are not indicated in the maintenance procedure.
TORQUE TABLES
Table 1 lists dry torque limits. Dry torque limits are used on screws that do not have lubricants applied to the threads. Table 2 lists wet torque limits. Wet torque limits are used on screws that have high-pressure lubricants applied to the threads. For metric fasteners, refer to table 3 for torque limit requirements.
HOW TO USE TORQUE TABLES
1. Measure the diameter of the screw you are installing.
Manufacturer’s marks may vary. Metric screws can be three grades: 8.8, Screws shown are all SAE Grade 5 (3-line). 10.9, and 12.9. Grades and manufacturer’s marks appear on the screw head.
8.8 10.9 12.9
STANDARD METRIC
2. Count the number of threads per inch.
3. Refer to the appropriate Torque Limits table. Under the heading SIZE, look down the left-hand column until you find the diameter of the screw you are installing. (There usually will be two entries beginning with the same size.)
4. In the second column under SIZE, find the number of threads per inch that matches the number of threads you counted in step 2.
5. To find the grade screw you are installing, match the markings on the head to the correct picture in CAPSCREW HEAD MARKINGS preceding the torque tables.
6. Look down the column under the picture you found in step 5. until you find the torque limit (lb-ft or N•m) for the diameter and threads per inch of the screw.
Table 1. Torque Limits for Dry Fasteners.
CAPSCREW HEAD MARKINGS
Manufacturer’s marks may
vary. Screws shown above
are all SAE Grade 5 (3-line).
TORQUE
SIZE SAE GRADE SAE GRADE SAE GRADE SAE GRADE
NO. 1 or 2 NO. 5 NO. 6 or 7 NO. 8
DIA. THREADS DIA. POUND NEWTON POUND NEWTON POUND NEWTON POUND NEWTON
INCHES PER INCH MILLIMETERS FEET METERS FEET METERS FEET METERS FEET METERS
1/4 20 6.35 5 7 8 11 10 14 12 16
1/4 28 6.35 6 9 10 14 12 16 14 19
5/16 18 7.94 11 15 17 23 21 28 24 33
5/16 24 7.94 12 16 19 26 24 33 27 37
3/8 16 9.53 20 27 30 41 40 54 45 61
3/8 24 9.53 23 31 35 47 45 61 50 68
7/16 14 11.11 30 41 50 68 60 81 70 95
7/16 20 35 47 55 75 70 95 80 108
1/2 13 12.70 50 68 75 102 95 129 110 149
1/2 20 55 75 90 122 100 136 120 163
9/16 12 14.29 65 88 110 149 135 183 150 203
9/16 18 75 102 120 163 150 203 170 231
5/8 11 15.88 90 122 150 203 190 258 220 298
5/8 18 100 136 180 244 210 285 240 325
3/4 10 19.05 160 217 260 353 320 434 380 515
3/4 16 180 244 300 407 360 488 420 597
7/8 9 22.23 140 190 400 542 520 705 600 814
7/8 14 155 210 440 597 580 786 660 895
1 8 25.40 220 298 580 786 800 1085 900 1220
1 12 240 325 640 868 860 1166 1000 1356
1 1/8 7 25.58 300 407 800 1085 1120 1519 1280 1736
1 1/8 12 340 461 880 1193 1260 1709 1440 1953
1 1/4 7 31.75 420 570 1120 1519 1580 2142 1820 2468
1 1/4 12 460 624 1240 1681 1760 2387 2000 2712
1 3/8 6 34.93 560 759 1460 1980 2080 2820 2380 3227
1 3/8 12 640 868 1690 2278 2380 3227 2720 3688
1 1/2 6 38.10 740 1003 1940 2631 2780 3770 3160 4285
1 1/2 12 840 1139 2200 2983 3100 4204 3560 4827
Table 2. Torque Limits for Wet Fasteners.
CAPSCREW HEAD MARKINGS
Manufacturer’s marks may
vary. Screws shown above
are all SAE Grade 5 (3-line).
TORQUE
SIZE SAE GRADE SAE GRADE SAE GRADE SAE GRADE
NO. 1 or 2 NO. 5 NO. 6 or 7 NO. 8
DIA. THREADS DIA. POUND NEWTON POUND NEWTON POUND NEWTON POUND NEWTON
INCHES PER INCH MILLIMETERS FEET METERS FEET METERS FEET METERS FEET METERS
1/4 20 6.35 4 6 6 8 8 11 9 12
1/4 28 6.35 5 7 7 9 9 12 10 14
5/16 18 7.94 8 11 13 18 16 22 18 24
5/16 24 7.94 9 12 14 19 18 24 20 27
3/8 16 9.53 15 20 23 31 30 41 40 54
3/8 24 9.53 17 23 25 34 30 41 44 60
7/16 14 11.11 24 33 35 47 45 61 55 75
7/16 20 25 34 40 54 50 68 60 81
1/2 13 12.70 35 47 55 75 70 95 80 108
1/2 20 40 54 65 88 80 108 90 122
9/16 12 14.29 50 68 80 108 100 136 110 149
9/16 18 55 75 90 122 110 149 130 176
5/8 11 15.88 70 95 110 149 140 190 170 231
5/8 18 80 108 130 176 160 217 180 244
3/4 10 19.05 120 163 200 271 240 325 280 380
3/4 16 140 190 220 298 280 380 320 434
7/8 9 22.23 110 149 300 407 400 542 460 624
7/8 14 120 163 320 434 440 597 500 678
1 8 25.40 160 217 440 597 600 814 680 922
1 12 170 231 480 651 660 895 740 1003
1 1/8 7 25.58 220 298 600 814 840 1139 960 1302
1 1/8 12 260 353 660 895 940 1275 1080 1464
1 1/4 7 31.75 320 434 840 1139 1100 1492 1360 1844
1 1/4 12 360 488 920 1248 1320 1790 1500 2034
1 3/8 6 34.93 420 570 1100 1492 1560 2115 1780 2414
1 3/8 12 460 624 1260 1709 1780 2414 2040 2766
1 1/2 6 38.10 560 760 1460 1980 2080 2820 2360 3200
1 1/2 12 620 841 1640 2224 2320 3146 2660 3607
Table 3. Torque Limits for Metric Fasteners.
CAPSCREW HEAD
MARKINGS
TORQUE
SIZE METRIC GRADE METRIC GRADE METRIC GRADE
8.8 10.9 12.9
DIA. DIA. POUND NEWTON POUND NEWTON POUND NEWTON
INCHES MILLIMETERS FEET METERS FEET METERS FEET METERS
.157 4 2 3 3 4 4 5
.197 5 4 5 6 8 7 9
.237 6 7 9 10 14 11 15
.276 7 11 15 16 22 20 27
.315 8 18 24 25 34 29 39
.394 10 32 43 47 64 58 79
.473 12 58 79 83 113 100 136
.552 14 94 127 133 180 159 216
.630 16 144 195 196 266 235 319
.709 18 190 258 269 365 323 438
.788 20 260 353 366 496 440 597
.867 22 368 499 520 705 678 919
.946 24 470 637 664 900 794 1077
1.064 27 707 959 996 1351 1235 1675
1.182 30 967 1311 1357 1840 1630 2210
TORQUE WRENCH ADAPTERS
Some tasks require the use of a torque wrench adapter when the nut or screw cannot be reached with a regular socket on the end of the torque wrench. These adapters add to the overall length of the torque wrench and make the dial or scale reading less than the actual torque applied to the nut or screw. To prevent overtorquing and damage to equipment, calculate correct dial or scale reading using the following conversion formula.
CONVERSION FORMULA
Corrected dial or scale readings are determined by the use of the following formula:
Corrected Required Length of torque wrench + Length of adapter
= torque value ÷ Length of torque wrench
reading
Example: Length of torque wrench 22 in. (55.9 cm)
Length of adapter 3 in. (7.6 cm)
In this example, the torque wrench measures 22 in. (55.9 cm) and the adapter is 3 in. (7.6 cm). The required torque is 19 lb-ft (25.8 N•m).
Corrected 19 lb-ft (25.8 N•m) ÷ 22 in. (55.9 cm) + 3 in. (7.6 cm) = 22 in. (55.9 cm) reading
Corrected 19 lb-ft (25.8 N•m) ÷ 25 in. (63.5 cm) = 22 in. (55.9 cm) reading
Corrected 19 lb-ft (25.8 N•m) ÷ 1.14 = reading
Corrected 17 lb-ft (23.1 N•m) = reading
Table 4. Torque Specifications.
ITEM LB-FT LB-IN N•m
Accessory drive pulley 40–45 — 54–61
Accessory drive pulley assembly 300–310 — 407–420
Accessory drive pulley locknut 300–310 — 407–420
Accessory drive pulley screws 40–45 — 54–61
Adapter 50 — 68
Adapter 20–25 — 27–34
Adjustable water pump pulley
Hex-head screw 12–15 16–20
—
Locknut 45–55 61–75
Aftercooler Cover capscrews 25 — 34
Air aftercooler cover screw 25 — 34
Air compressor support 30–35 — 41–48
Air crossover hose clamp — 30–35 3–4
Brass filter fittings 30–40 — 41–54
Cam follower capscrews 30–35 — 41–48
Camshaft support screws 25 — 34
Compact head capscrews 15–19 — 20–26
Connecting rod nut
Step 1 Torque to 70–75 95–102
Step 2 Torque to 140–150 190–203
Step 3 Loosen all completely — —
Step 4 Torque to 25–30 34–41
—
Step 5 Torque to 70–75 95–102
Step 6 Torque to 140–150 190–203
Cover screw — 96–132 11–15
Cylinder head bolt 15–19 — 20–26
Cylinder head capscrews
Step 1 20–25 27–34
Step 2 80–100 109–136
—
Step 3 265–305 359–414
Diffuser plate — 60–84 7–10
Flywheel bolt 19–21 — 26–29
Flywheel capscrews 190–200 — 258–271
Flywheel capscrews with hardened washers 200–220 — 271–298
Table 4. Torque Specifications (Contd).
ITEM LB-FT LB-IN N•m
Flywheel housing capscrews 140–160 — 190–217
Front cover 45–55 — 61–75
Front engine mount nut 270–295 — 366–400
Front support 55 — 75
Fuel crossover capscrews 3 — 4
Fuel filter bracket capscrews 25 — 34
Fuel fittings — 150 17
Fuel injector orifice plug — 8–10 11–14
Fuel pump front cover capscrews 9–11 — 12–15
Fuel pump mounting capscrews 30–35 — 41–48
Gear pump capscrews 11–13 — 15–18
Governor spring pack capscrews 9–11 — 12–15
Hose clamps
Water pump mounting 30–35 41–48
—
Water manifold 30–35 41–48
Impeller housing screws 60 7
Impeller locknut 30 — 41
Injector adjusting screw — 72 8
Injector stand stud — 75 9
Intake manifold 20–25 — 27–34
Locknut, V-band clamp — 58–68 7–8
Locknuts with ST-669 adapter 30–35 — 41–48
Main bearing capscrews
Step 1 Torque to 85 115
Step 2 Torque to 250–260 339–353
Step 3 Loosen all 3 to 5 threads — —
Step 4 Torque to 85 — 115
Step 5 Torque to 250–260 339–353
Mounting capscrews 20–25 — 27–34
Mounting locknut 22–48 — 30–65
Oil cooler mounting capscrew 30–35 — 41–48
Oil drain fitting 50 — 68
Oil inlet fitting 20–25 — 27–34
Table 4. Torque Specifications (Contd).
ITEM LB-FT LB-IN N•m
Oil pan
Captive washer screws 35–40 48–54
—
Hex-head screws 15–20 20–27
Oil pan drainplug 60–70 — 81–95
Oil pump mounting capscrews 35–45 — 48–61
Oil suction tube mounting capscrews 30–35 — 41–48
Piston cooling nozzle hex-head screw 8–12 — 11–16
Rear engine mount nut 270–295 — 366–400
Retainer 53–57 — 72–77
Rocker cover capscrews
Cork casket 12–17 — 16–23
Cork and cubber casket — 75–95 9–11
Rocker lever housing capscrews 55–65 — 75–88
Rotor locknut 20–24 — 27–33
Support screw 30–35 — 41–47
Throttle shaft plug — 40–55 5–6
Transmission bolt 60 — 80
Transmission drainplug 18–24 — 25–32
Transmission main housing bolt 40 — 54
Universal joint bearing strap screw 36 — 49
Unloader body capscrews — 96–120 11–14
Valve crosshead nuts with ST-669 adapter 22–26 — 30–35
Valve locknuts 40–45 — 54–61
V-band clamp — 32–36 3–4
V-band clamp nut 10 — 14
Vibration damper bolts 190 — 258
Vibration damper mounting capscrews 180–200 — 244–271
Water header plates — 72–96 8–11
Water inlet and outlet flange mounting
27–32 — 37–43
Capscrews
Water inlet screw 32 — 43
Water outlet connection 15–20 — 20–27
Water outlet screw 20 — 27
END OF WORK PACKAGE