Demco AC20037 Lawn Mower User Manual


 
Page 13
BOLT TORQUE
TORQUE DATA FOR STANDARD NUTS, BOLTS, AND CAPSCREWS.
Tighten all bolts to torques specified in chart unless otherwise noted. Check tightness of
bolts periodically, using bolt chart as guide. Replace hardware with same grade bolt.
NOTE: Unless otherwise specified, high-strength Grade 5 hex bolts are used throughout
assembly of equipment.
Bolt Torque for Standard bolts *
GRADE 2 GRADE 5 GRADE 8
A lb-ft (N.m) lb-ft (N.m) lb-ft (N.m)
1/4 6 (8) 9 (12) 12 (16)
5/16 10 (13) 18 (25) 25 (35)
3/8 20 (27) 30 (40) 45 (60)
7/16 30 (40) 50 (70) 80 (110)
1/2 45 (60) 75 (100) 115 (155)
9/16 70 (95) 115 (155) 165 (220)
5/8 95 (130) 150 (200) 225 (300)
3/4 165 (225) 290 (390) 400 (540)
7/8 170 (230) 420 (570) 650 (880)
1 225 (300) 630 (850) 970 (1310)
Torque figures indicated are valid for
non-greased or non-oiled threads and
heads unless otherwise specified.
Therefore, do not grease or oil bolts or
capscrews unless otherwise specified
in this manual. When using locking
elements, increase torque values
by 5%.
* GRADE or CLASS value for bolts
and capscrews are identified by their
head markings.
Torque Specifications
CLASS 8.8 CLASS 9.8 CLASS 10.9
A lb-ft (N.m) lb-ft (N.m) lb-ft (N.m)
6 9 (13) 10 (14) 13 (17)
7 15 (21) 18 (24) 21 (29)
8 23 (31) 25 (34) 31 (42)
10 45 (61) 50 (68) 61 (83)
12 78 (106) 88 (118) 106 (144)
14 125 (169) 140 (189) 170 (230)
16 194 (263) 216 (293) 263 (357)
18 268 (363) -- -- 364 (493)
20 378 (513) -- -- 515 (689)
22 516 (699) -- -- 702 (952)
24 654 (886) -- -- 890 (1206)
Bolt Torque for Metric bolts *
GRADE-2 GRADE-5 GRADE-8
8.8
10.9
9.8
CLASS 8.8 CLASS 9.8 CLASS 10.9