Dodge D250 1990 Service Manual page 429

Fuel System Malfunction - Diagnosis
Page 14-10
Fuel System
DODGE Turbo Diesel
®
To verify that the injection pump is timed correctly, first check
the alignment marks on the pump flange and gear housing.
Note: The alignment mark is unique to each engine.
The pump has a provision for locking the pump shaft at a
position corresponding to top-dead-center for Cylinder
Number 1.
New and reconditioned pumps should be received with the
shafts locked in this position.
Caution: If the timing pin is Incorrectly located on the
gear housing, the timing procedure will not ensure that
the pump is timed correctly.
After precisely locating TDC for Cylinder Number 1, the factory
positions the timing pin assembly to the gear housing using the
timing pin and the hole in the camshaft gear, if the gear
housing or timing pin assembly are removed, the same
precision is required to relocate it.