Engine running hot...

[wmah]

I don't know what my gadge reads on mine cause it has a bad connection somewhere from the sending unit to the gadge or it is a bad sending unit or a bad gadge. I have been in ones where it works right and it can be anywhere from 175 to 210, I think it depends on the thermostat that is in it. You may want to replace it and see what happens. You may also have extra valves under the hood to shut the water off. Mine has the one inside and too under the hood.
These things still get warm inside even with them closed cause the heat comes from the firewall and the floor. I noticed a big difference with noise and heat from the floor after I put padding down and carpet.

[hoser]

I am not sure how your heat is plumbed but on my bus their is also 2 water valves under the hood you can turn off to stop the heat!

I drove my bus on a 98 degree day once and cooked both feet from the heat coming off the floor and firewall I dont think they are insulated.