Detroit Diesel Series 149 Torque Specifications

June 9, 2023

	Detroit Diesel Series 149 Torque Specifications
Thread Size (in.)	Description	Torque Specifications
Thread Size (in.)	Description	lb-ft	N-m
1/4-28	Standard Torque Specification	8-10	11-14
1/4-28	Screw-Inj. Rack Control Lever	2-3	3-4
5/16-18	Standard Torque Specification	13-17	18-23
	Bolt-Turbocharger Back Plate Assembly to Center Housing	7-10	9-14
	Bolt-Turbocharger Back Plate Assembly to Center Housing	7-10	9-14
5/16-24	Standard Torque Specification	15-19	20-26
	Nut-Lock-Push Rod	15-19	20-26
	Nut-Lock Valve Bridge Adj. Screw	20-25	27-34
	Bolt-Camshaft Drive Coupling	20-25	27-34
3/8-16	Standard Torque Specification	30-35	41-47
3/8-24	Standard Torque Specification	35-39	47-53
	Nut-Water Pump to Front Cover	25-30	34-41
	Bolt-Camshaft Drive Coupling	45-50	61-68
	Bolt-Fuel Pump Drive Coupling Retainer	50-55	68-75
7/16-14	Standard Torque Specification	46-50	62-68
	Bolt-Blower Hold Down	50-55	68-75
	Bolt-Injector Hold Down Clamp	46-50	62-68
7/16-20	Standard Torque Specification	57-61	77-83
	Nut-Fuel Jumper Line to Injector	18-22	24-30
	Nut-Water Pump Shaft (Lock)	40-45	54-61
	Bolt-Crankshaft Flange Coupling	70-80	95-108
1/2-13	Nut-Exhaust Manifold Standard	32-38	43-52
	Nut-Fuel Manifold Connector	35-40	47-54
	Bolt-Fan Blade to Pulley Hub	71-75	96-102
	Bolt-Cylinder Block	75-85	102-115
	Bolt-Crankshaft and Camshaft Idler Hub Center Bolt	80-90	108-122
	Bolt-Camshaft Bearing Cap	90-100	122-136
	Bolt-Rocker Arm Shaft	90-100	122-136
1/2-20	Standard Torque Specification	83-93	113-126
	Nut-Exhaust Manifold Stud	35-40	47-54
	Bolt-Cylinder Block	85-95	115-129
	Bolt-Crankshaft Flange Coupling	100-110	136-149
9/16-12	Standard Torque Specification	90-100	122-136
	Bolt-Blower Hold Down	75-85	102-115
	Bolt-Main Bearing Cap	120-130	163-176
9/16-18	Standard Torque Specification	107-117	145-159
	Nut-Crankshaft Bearing Cap	130-140	176-190
	Bolt-Cylinder Head	90-100*	122-136
5/8-11	Standard Torque Specification	137-147	186-199
5/8-18	Standard Torque Specification	168-178	228-241
	Bolt-Crankshaft Adaptor	175-185	237-251
	Bolt-Flywheel (Self Locking)	180-190	244-258
	Bolt-Vibration Damper	180-190	244-258
	Nut-Raw Water Pump Shaft Retaining	25-30	34-41
	Nut-Alternator Pulley	70-80	95-108
	Nut-Special Self Locking Nut (10SI Alternator)	40-60	54-81
	Bolt-Oil Pick-Up Assembly	20-25	27-34
3/4-10	Nut-Flange Mounted Air Compressor Drive Shaft	70-80	95-108
3/4-10	Bolt-Crankshaft Main Bearing	280-290	380-393
3/4-16	Standard Torque Specification	290-300	393-407
	Accessory Drive Pulley Nut	120-140	163-190
3/4-18	Nut, Dipstick Tube	30-35	41-47
7/8-14	Standard Torque Specification	475-485	644-658
1 1/4-7	Bolt-Crankshaft Pulley Retainer	450-500	610-678
1 5/16-18	Nut-Blower Timing Gear	200-250	271-339
2.548-18	Nut-Idler Gear Bearing (Lock)	280-300	380-407
3.137-12	Nut-Camshaft Gear Bearing (Lock)	280-300	380-407
	* Follow cross-pattern bolt torquing sequence and multiple stage process leading up to the final torque process. After final torque is achieved, turn each bolt 90 degrees (1/4 turn clock-wise) with a single smooth pull of the wrench.

	Detroit Diesel Series 149 Pipe Plug Oil Cooler Torque Specifications
Plug Size (in.)	Description	Torque Specifications
Plug Size (in.)	Description	lb-ft	N-m
1 1/16-16	Plug-Oil Cooler Bypass Valve	80-90	108-122
1 1/4-16	Plug-Oil Filter Bypass Valve	95-105	129-142
1 1/2-6	Plug-Oil Filter Bypass Valve	110-130	149-176
2-12	Plug-Oil Filter Bypass	130-150	176-203

	Detroit Diesel Series 149 Pipe Plug Torque Specifications

Plug Size (in.)	Description	Torque Specifications
Plug Size (in.)	Description	lb-ft	N-m
1/8-27	Plug-Pipe (3/4 Taper)	10-12	14-16
1/4-18	Plug-Pipe (3/4 Taper)	14-16	19-22
1/4-18	Plug-Pipe (7/8 Taper)	14-16	19-22
3/8-18	Plug-Pipe (3/4 Taper)	18-22	24-30
3/8-18	Plug-Pipe (7/8 Taper)	18-22	24-30
1/2-14	Plug-Pipe (3/4 Taper)	23-27	31-37
1/2-14	Plug-Pipe (7/8 Taper)	23-27	31-37
3/4-14	Plug-Pipe (3/4 Taper)	33-37	45-50
3/4-14	Plug-Pipe (7/8 Taper)	33-37	45-50
1-11 1/2	Plug-Pipe (3/4 Taper)	75-85	102-115
1-11 1/2	Plug-Pipe (7/8 Taper)	75-85	102-115
1 1/4-11 1/2	Plug-Pipe (3/4 Taper)	95-105	129-142
1 1/2-11 1/2	Plug-Pipe (3/4 Taper)	110-130	149-176
1 1/2-11 1/2	Plug-Pipe (7/8 Taper)	110-130	149-176

	Detroit Diesel Series 149 Stud Specifications

Plug Size (in.)	Description	Torque Specifications
Plug Size (in.)	Description	lb-ft	N-m
1/2-13	Stud-Exhaust Manifold	35-40	47-54