TM 5-2420-230-24-2
Cylinder Head (002-004)
B3.9 and B5.9 Series Engines
Page 2-10
Section 2 - Cylinder Head - Group 02
Use a straightedge and a feeler gauge to inspect the cyl-
inder head combustion surface for flatness.
Cylinder Head Flatness (6B engine)
mm
in
End-to-End
0.305
MAX
0.012
Side-to-Side
0.076
MAX
0.003
Cylinder Head Flatness (4B engine)
mm
in
End-to-End
0.203
MAX
0.008
Side-to-Side
0.305
MAX
0.012
Cylinder Head Capscrews
Inspect the cylinder head capscrews for damaged threads,
corroded surfaces, or a reduced diameter (due to capscrew
stretching).
Do not reuse cylinder head capscrews under the following
conditions:
Visible corrosion or pitting exceeds 1 sq cm [0.155
sq. in] in area
Acceptable 3/8 x 3/8 inch
Unacceptable 1/2 x 1/2 inch
Visible corrosion or pitting exceeds 0.12 mm [0.005
in] in depth.
Visible corrosion or pitting is located within 3.2 mm
[1/8 in] of the fillet.
Visible corrosion or pitting is located within 3.2 mm
[1/8 in] of the threads.
Stretched beyond "free-length" maximum. Refer to
the measurement procedure below:
L-806