SERVICE MANUAL
CYLINDER HEAD & VALVES
Section 3
The cylinder head, cylinder head gasket and cylinder
head coolant directors have been revised for all 400
Series Engines. The 12 coolant holes in the bottom deck
of the cylinder head have been enlarged from 19.05 mm
(.750 in.) to 23.80 mm (.937 in.) in diameter (Refer to
Fig. 5)
Figure 5. - Cylinder Head Bottom View
of Deck With Coolant Hole Locations
The outer diameter of the press-fit coolant directors used
in these coolant holes has also been increased in size
from 19.15 mm (.754 in.) to 23.90 mm (.941 in.).
The twelve cylinder head gasket coolant holes have
been enlarged to accommodate the larger coolant hole
size.
IMPORTANT: The new style cylinder head gasket (IH
Part No. 676 108 C2) and cylinder head gasket
package (IH Part No. 674 398 C95) may be used with
either the old or new style cylinder head. The old
style cylinder head gasket (IH Part No. 676 108 C1)
and cylinder head gasket package (IH Part No. 674
398 C94) can only be use with the old style cylinder
head.
The new style cylinder head can be identified by the
casting number (see chart) located on top of the cylinder
head at intake side between number four and five nozzle
locations (Refer to Figure 6).
Figure 6. - Cylinder Head Production
Part No. Location
1.
Number Four Nozzle Bore
2.
Casting Number Location
3.
Number Five Nozzle Bore
CGES-185-3
PRINTED IN UNITED STATES OF AMERICA
Page 3
