ANGLE 3564884 - Caterpillar

Illustration 1. Comparison of former (left) and new (right) nonmetallic impellers.
Illustration 2. New nonmetallic impeller with chamfered hub.A new 9Y5647 Water Pump Group is available that uses a 9Y5652 Adapter (cast iron) and 9Y5646 Pump Group. See Illustration 3. This adapter (1) may reduce cavitation erosion when the recommended ethyleneglycol mixture is not used in the cooling system. Coolant conditioner MUST always be used in the 3400 Family of Engines.
The new 9Y5646 Water Pump Group has a cast iron impeller (2). The 9Y5651 Impeller (cast iron) can be used in extreme load applications. The cast iron impeller is a solid iron casting which would eliminate hub separation as a possible problem.
The 9Y5652 Cast Iron Adapter is not compatible with the 7C5479 Impeller because of possible vane to adapter interference.
Illustration 3. Location of cast iron impeller and adapter.The new 9Y5647 and 9Y5646 Water Pump Groups are available for parts service. The 9Y5646 Water Pump Group is available as remanufactured 0R2856 Water Pump Group.