Dodge D250 1990 Service Manual page 349

Alternative Repair Procedures
Page9K-l8
Base Engine Components
DODGE Turbo Diesel
If the valve guide bores are larger than the worn limit, the cylinder head must be machined for service valve guides.
New valve guides must be reamed to size after they are installed.
Note: if the cylinder head needs sen/ice valve guides and valve seat inserts, the valve guides should be installed
first.
Valve Guides
• Intake (Thick wall)
• Exhaust (Thick wall)
• Intake and Exhaust (Thin wail)
Service Valve Guides - Thin Wall
Machine the cylinder head valve guide bores to Dimension A.
A = 11.125 + 0.013mm [.4380 + .0005] in diameter
Service valve guides must be centered with vaive seats within
0.35mm [01378 inch] diameter and are to be square with the
combustion face within 0.10mm [.0004 inch] at 50.0mm
[1.9685 inch] radius.
the valve guides as illustrated.
Lubricate with oil and press the guides flush to the bottom
of the bosses.
12.00 ± 0.75mm [.4724 + .0295 inch] reference
Trim off flush to top of guide bosses if necessary.
8.029 ± 0.010mm [.3161 ± .0004 inch]
Note: The valve guide bore must be centered with the valve
seat within 0.35mm [0.0138 inch] diameter and must be square
with the combustion face within .010mm [0.004 inch] at
50.0mm [2.0 inch] radius.
Service Valve Guides - Thick Wail
Machine the cylinder head valve guide bores to Dimension A.
A « 14.000 ± 0.013mm [0.5512 + .0005 inch] diameter
Valve guides must be centered with valve seats within 0.35mm
[.01378 inch] diameter and must be square with the
combustion face within 0.10mm [.0004 Inch] at 50.0mm
[1.9685 inch] radius.