Cfmoto vnight coolant change advice

[Engineern6719]

I have just gone through the process of flushing and replacing the engine coolant.It was a very difficult job bleeding the system of air but eventually got there.The service manual for the engine doesn't mention the method used to replace the coolant.However when I examined the diagram of the water pump there are three bolts (items 6)for disassembling the pump plus an extra bolt at the top of the pump that is not mentioned in the service manual.
Would somebody know if this extra bolt in the case of the pump is a bleed screw for the coolant?