Yes, I installed the water pump in lieu of the MaxStat. The pump circulates coolant all the time at full rate, even when the machine is at idle. Also, even if there is only a hint of heat in the coolant, it's better to circulate that then have to wait until the machine comes up to temp and thermostats start opening. Scott @ Couper's Products said they will likely make the water pump THE option (over the MaxStat) for many kits. Call them and ask to talk to Scott - he installs these heaters for customers who bring their rig to them.