Dauntless intake manifold question

Hey guys. I haved tried searching, but can't find a good answer. On a stock 225 intake manifold, what is the plug/port on the passenger side rear for? It is right near the last intake bolt. Is it for water (which I assume) or is it possibly vacuum? I am looking for a spot to install my electric fan thermostat sender. Thanks!

 

Heater hose.

 

My heater hose connects to the water pump and next to the thermostat housing. But if it is a water jacket, that will work perfectly for me. I pulled the plug, but seems how there is very little antifreeze in the engine right now, I can't tell if this is an access to the coolant.

 

I have seen at least one Dauntless 225 with the heater hose near the thermostat, but most of them I have seen have the heater hose connected to the port at the passenger rear of the intake manifold as you describe.
To install an thermostat sender I think I would pick the port near the thermostat, because the coolant circulates more past that point.

Don

 

:iagree:

 

x3 Move the heater hose back to the rear port where it is supposed to be and use the port next to the thermostat for the switch.

 

Thanks guys. That's what I'll do!