dual water pump pulley?

[tdw6974]

If the water pump pulley is smaller, then it's making the pump turn faster.

Is that a pump pulley or an eccentric shaft pulley? And how does it use dual belts if they're not both replaced?

GA

Greg, that is the water pump pulley. The eccentric pulley and alternator pulley are both dual groove to enable use of 2 belts as a "fail safe" also installing a Water pressure warning light.