SERVICE MANUAL
VALVE TRAIN - CAMSHAFT, TAPPETS & PUSH RODS
Section 4
400 SERIES TAPPET REVISIONS WHICH OCCURRED
IN PRODUCTION
I.
REVISED
400
SERIES
TAPPET
WITH
INCREASED DIAMETER (Refer to Fig. 7).
The revised tappet measuring 28.4480/ 28.4353 mm
(1.1200/1.1195 in.) has been released into production
and service for all 400 Series Diesel Engines. The new
tappet provides improved tappet life. The following
changes occurred to accommodate the larger tappet:
•
Introduce a revised camshaft with a wide cam
lobe and increased forging diameter (see Fig.
6).
•
Introduce a revised crankcase by increasing the
tappet bore diameter (see Section 6, Figure 4).
400 SERIES CAMSHAFT REVISIONS WHICH
OCCURRED IN PRODUCTION
I.
Revised Intake Ramp Height
The revised intake ramp height of the camshaft
requires the engine gear train timing adjustment
specification and intake valve lash specification
be changed.
IMPORTANT: Refer to Section 3 for current
engine gear train timing and valve lash
adjustment specifications and procedures.
DISPLACED STYLE CAMSHAFT (IH Part No. 691488C1)*
*NON-SERVICEABLE PART NO.CG-7912
Figure 6. - Camshaft Identification
CGES-185-3
PRINTED IN UNITED STATES OF AMERICA
Page 3
