Usage:
3306 (69D, 76R),
G3306 (4DL),
3306B (5KD, 63Z) 3306C (7RJ, 9TL, 3KS, 2AZ) Truck Engines
Reference: See Truck Engine New article entitled; "History Of Pump Impeller (Water Pump) Changes" in this issue.
Description of Change: An improved pump impeller (water pump) is in production and available for the above truck engines. The improved pump impeller significantly reduces the possibility of down time caused by cracking or loosening of the water pump impeller resulting in engine overheating. The pump impeller is made of an improved plastic material called PolyEther Sulfone (PES). PES consists of a glass reinforced plastic resin.
The improved pump impeller is superior in structural properties to earlier plastic or cast iron pump impellers and is less than half the weight of the cast iron pump impeller. Inertia is reduced because of the lighter weight. The bolt fastening the pump impeller to the pump shaft is less likely to loosen. The improved PES plastic material allows the use of standard 3/8 inch bolt torque [47 ± 9 N·m (35 ± 7 lb ft)] instead of the special low torque [39 ± 2 N·m (29 ± 1 lb ft)] required to prevent the cast iron hub from cracking.
NOTE: When comparing the improved pump impeller to the earlier brown plastic pump impeller, the improved pump impeller is much superior. The improved pump impeller will not break even when dropped and will not separate at the insert joint (molded in metal).
Adaptable To: The improved 134-7422 Pump Impeller (Water Pump) is adaptable to the above machine engines back to first production. The 134-7422 Pump Impeller is an improvement to the earlier 4W-9645, and 7N-5910 Pump Impellers. See the chart for truck engine effectivity.
NOTE: The 4W-9645 Pump Impeller was never used on truck engines produced in Japan or Brazil.
NOTE: The effectivity in the chart is for truck engines produced in Mossville only. Other effectivity is not available.