KIT-GASKET-OCL 2971740 - Caterpillar

Illustration 1 g03595417
Current return check valve (1) Bolt (2) Spring holder (3) Nut (4) Plug
Illustration 2 g03595418
Improved return check valve (1) Bolt (2) Spring holder (4) PlugRefer to Table 1 for the part number of the improved return check valve.
Table 1
Part Numbers for Improved Return Check Valve    
New Part Number     Description     Former Part Number     Description    
455-3961     Check Valve Gp     335-0300     Check Valve Gp    Rework Improvements
Bolt:
Change bolt material from "S45C" to "SCM435" to increase stress limit.
Eliminate bolt thread to reduce stress concentration on pin.Nut:
Eliminate nut from return check valve setup.Spring Holder:
Reduce width of internal machining needed to contain the improved bolt.Plug:
Reduce internal dimension to prevent the spring holder from moving.