Recommended valve for engine coolant fluid

[B_Hunter45]

Hi,

I am going to replace my hot water heater. There are two 5/8 water line to and from the engine delivering the engine coolant to the heat-exchanger. I want to install valves on these lines to be able to service the heater in the future.
This is a fresh water cooling system, the fluid running in those pipes is engine coolant.
Which type of valve is recommended? plastic/PVC? brass? Bronze?
Thanks

[DougR]

I use 5/8" brass ball valves with hose barbs and quality hose clamps. Bronze or stainless valves will also suffice, but I would be cautious with plastic as the coolant temp exiting the engine is probably close to 180degrees F.

Place the valves close to the engine so you can isolate as much hose as possible in the event of a hose problem.

DougR

[Cat36Mahalo]

Make sure you can shut them off. My wh lines are the thermostat bypass line. If you shut them off you would need a third valve to connect the two line. On the engine side.