Air Valve - Factory Overhauled Yak 52
Main or Emergency Air Valve in either cockpit.
Legend has it these can be serviced...That hex on the valve gland looks like it would come so easily to the crescent wrench, right?
And in all probability that's where the corrosion is. When they become hard to turn, internal corrosion has the upper hand and it will not get better with time or brutality.
Just like the Pneumatic start valve, somebody at the factory is assembling these using tremendous torques, since this valve sees full system pressure.
We receive these as pictured, overhauled and tested by the factory. However in some cases the Tees and Valve Handle may not be present on your valve.