M925 Air Leak, top of engine, looks like some kind of brass valve, stuck?

[jonsm114]

In top of engine, and appears to be made of brass attached to top water hose manifold. Has a air line running to it. Bleeding air all the time.

What to do?

Remove and clean? Lubricate?

Thanks for any help.

Jon

 

[Scar59]

That is the shutter stat that controls the cooling fan clutch. Disassemble , clean, replace o rings , lube, reinstall , top off coolent fluid , start engine, cross fingers, and read the tech manual. If fix is " no joy", replace with new.