TM 5-2420-230-24-2
Section V - Engine Component Specifications - Group 18
Component Specifications and Torque Values
B Series
Page V-25
Component or Assembly (Procedure)
Ref.No./Steps
Metric
U.S.
Valve Insert Bore I.D. (Standard Insert)
46.987 mm
MIN
1.8499 in
47.013 mm
MAX
1.8509 in
Note: Refer to Cylinder Head - Oversize
Valve Seat Installation for oversize valve
insert dimensions.
Valve Seat Grinding Depth
B
0.254 mm
MAX
0.010 in
Seat grinding depth is the difference in
dimension `B' before and after grinding.
Cylinder Head Cracks - Reuse Guidelines
These guidelines apply only to cracks extending from the injector bore to the intake valve seats.
Replace cylinder heads which exhibit valve bridge cracks in any other location.
The reuse guidelines for a cylinder head with a crack extending from the injector bore to the intake
valve seat are as follows:
If the crack does not extend into the valve seat, the head is reusable.
If the crack extends into or through the valve seat, the head must be repaired by installing a valve
seat insert as described in the Alternative Repair Manual, Bulletin No. 3810234.
Cylinder Head - Torque Values
Cylinder Head Mounting Capscrew (Tighten
in the Sequence Shown)
Step
1
- All
90
Nm
66
ft-lb
Step
2
- Recheck to
90
Nm
66
ft-lb
Step
3
(Long Capscrews Only)
120
Nm
90
ft-lb
Step
4
(Long Capscrews Only) - Recheck to
120
Nm
90
ft-lb
Step
5
- Rotate 90 degrees - All
Rocker Levers and Pedestals
Rocker Lever Bore Diameter
19.000
MIN
0.7480 in
19.051
MAX
0.7500 in
L-499
