SERVICE MANUAL
CLEANING AND INSPECTION
Section 3
CAMSHAFT
Injection pump part numbers 1 802 604 C91, 1 802
605 C91, 1 802 606 C91, 1 802 607 C91, 1 802 608
C91, 1 802 643 C91 and 1 802 995 C91 were built with
old style camshaft (Figure 6) and old style fuel return
hose with a .062 in. diameter orifice (Figure 7). If
camshaft replacement is required order new style
camshaft (IH P/N 1 806 505 C1) and new style fuel
return hose with a .046 in. diameter orifice (IH P/N 1 806
503 C1). The new camshaft provides improved fuel
supply pump performance and the reduced orifice
diameter is required to maintain appropriate fuel return
flow to the tank and internal fuel injection pump housing
pressures.
IMPORTANT
THE NEW CAMSHAFT (1 806 505 C1)
MUST USE THE FUEL RETURN HOSE
WITH .046 IN. DIAMETER ORIFICE (1
806 503 C1). CONVERSELY THE OLD
CAMSHAFT (691 248 C1) MUST USE
THE FUEL RETURN HOSE WITH .062
IN. DIAMETER ORIFICE (1 802 897
C1).
NOTE: With the new camshaft and fuel return hose
added to any of the injection pumps listed above it
becomes a C92 suffix pump. This is important when
determining correct supply pump pressure on individual
pump data sheets (Section 5 - Calibration).
Figure 6. Camshaft Identification
Figure 7. Old vs. New Fuel Return Hose with Orifice
Fitting
CGES-375
Printed in United States of America
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