General Bolts and Nuts Tightening Torque Standard Bolts and Nuts New Tightening Method-By Use of Bolts to be Tightened in Plastic Area A new type of bolts, to be tightened in plastic area, is currently used in some parts of the engine. The tightening method for the bolts is different from the conventional one. Be sure to observe the method described in the text when tightening the bolts. Service limits are provided for the bolts. Make sure that the service limits described in the text are strictly observed. Area where the bolts are in use:
(1) Cylinder head bolts (2) Main bearing cap bolts (3) Connecting rod cap bolts Tightening method After tightening the bolts to the specified torque, tighten them another 90° or 180° (twice 90°). The tightening method varies on different areas. Observe the tightening method described in the text.
G424 Service Manual General Information 11 Nominal diameter Pitch Torque, kg•m (lb•ft) [N•m] Bolt, stud, nut (with spring washer) Flange bolt, flange nut Head mark 4 Head mark 7 Head mark 10 Head mark 4 Head mark 7 M5 M5 - 0.5 (0.5) [3.6] - - 0.6 (4.3) [5.9] M6 M6 - 0.9 (6.5) [8.8] 1.2 (8.7) [12] - 1.0 (7.2) [9.8] M7 M7 1.2 (8.7) [12] 2.2 (15.9) [22] 3.0 (21.7) [29] 1.3 (9.4) [13] 2.4 (17.4) [24] M8 M8 2.5 (18.1) [25] 4.5 (32.5) [44] 6.0 (43.4) [59] 2.6 (18.8) [25] 5.0 (36.2) [49] M9 M9 4.2 (30.4) [41] 8.6 (60.0) [81] 10.7 (77.4) [105] 4.7 (34.0) [46] 9.5 (68.7) [93] M10 M10 7.3 (52.8) [72] 14.0 (101.3) [137] 14.5 (104.9) [142] - - Tapered Threads Size Torque, kg•m (lb•ft) [N•m] Material of internal threads:
Aluminum alloy Material of internal threads: Cast iron or steel NPTF 1/16 0.5 to 0.8 (3.6 to 5.8) [5 to 8] 0.8 to 1.2 (5.8 to 8.7) [8 to 11] PT 1/8 0.8 to 1.2 (5.8 to 8.7) [8 to 11] 1.5 to 2.2 (10.8 to 15.9) [15 to 21] PT 1/4 2.0 to 3.0 (14.5 to 21.7) [20 to 29] 3.5 to 4.5 (25.3 to 32.5) [34 to 44] NPTF 1/4 2.0 to 3.0 (14.5 to 21.7) [20 to 29] 3.5 to 4.5 (25.3 to 32.5) [34 to 44] PT 3/8 4.0 to 5.5 (28.9 to 39.8) [39 to 59] 5.5 to 7.5 (39.8 to 54.2) [54 to 73] PT 1/2 7.0 to 10.0 (50.6 to 72.3) [69 to 98] 12.0 to 16.0 (86.8 to 115.7) [118 to 156]