Usage:
3306 Truck Engines
Description of Change: New oil pump groups are being used. The new oil pump groups do not have a key between the oil pump drive gear and the oil pump drive shaft. See Illustration 1. These pump groups rely on the taper fit between the drive gear and the pump drive shaft to transmit the torque to run the pump. The former pump groups used a key, along with the taper fit between the drive gear and pump drive shaft, to help transmit the torque to drive the oil pump. See Illustration 2.
Illustration 1. View of area where 6I1343 and 6I1346 oil Pump Groups drive shafts (3) are fastened to the oil pump drive gear (2) by bolt (1).
Illustration 2. View of area where 4P4020 and 4P4021 Oil Pump Groups drive shafts (3) are fastened to the oil pump drive gear (2) by bolt (1) and key (4).
Adaptable To: The new 6I1343 and 6I1346 Oil Pump Groups are direct replacements for the former 4P4021 and 4P4020 Oil Pump Groups respectively. The former oil pump groups are canceled.
The part numbers of the 0R0920 and 0R2560 Remanufactured Oil Pump Groups for these engines have not changed. These remanufactured pump groups may or may not have a oil pump drive shaft with a key slot. Either configuration can be used without a key. Either configuration can be used with a drive gear with or without a key slot. Bolt (1) should be tightened to 47 ±9 N·m (35±7 lb ft) whether or not there is a key.