R2.8 CM2220 R101B Cooling System Section 1 - Installation by Subsystem Page 1-19 Figure 3 - Electric Fan Relay 1 Fan Ground White wire, pin 34 2 To fan 3 Battery, 12 volt power 4 High Speed Signal Yellow wire, pin 33 5 Coil. Adaptations to use a mechanical fan may be available from aftermarket suppliers. It is recommended to utilize Specialty Equipment Market Association (SEMA) members, as the R2.8 CM2220 R101B computer-aided design (CAD) is available to reputable suppliers through their tech transfer program. Should a mechanical fan drive be required, the information in Figure 4 can be used to direct mount a cooling fan or a clutching mechanism for the cooling fan.
The engine fan hub pulley rotates counterclockwise . The belt driven front engine accessory drive (FEAD) system is capable of driving up to a 15 HP cooling fan. The fan drive hub will contain a bearing spacer that must be discarded, enabling the 25.4 mm [1 in] pilot to be used for the cooling fan or fan clutch. The pilot length is 10 mm [0 .4 in] thick. The bending moment imposed on the fan hub by the weight of the fan and the length of the spacers must not exceed 2.5 N•m (1.8 ft-lb) and spacer length must not exceed 76.2 mm [3 in]. To buy Cummins Parts and Service Manuals, Training Guides, or Tools go to our website at https://store.cummins.com