Usage:
All Direct Injection 3406 Truck Engines
Description of Change: New inner and outer springs are used in the governor and fuel pump drive groups for all direct injection 3406 Truck Engines. The new springs are part of the timing advance components.
The new outer springs have approximately 1.2 mm (.05) smaller outside diameter. This gives added clearance between the springs and the weights. The new inner springs also have smaller outside diameters, and they have more coils (turns).
The load characteristics of the new springs are the same as the load characteristics of the former springs.
Formerly, springs with larger outside diameters were used. Contact between the outer springs and the weights caused the outer springs to wear and shortened their service life.
Adaptable To: The new parts, used together, are direct replacements for the former parts as shown in the chart.