I'm getting ready for a short stay haul out in about a month during which time I'm planning to replace the stern tube hose and re-pack the stuffing box (plus a few other minor tasks, time permitting). I've been getting parts, making some tools I'll need and formulating the plan of attach.
While discussing the procedure with my buddy who'll be helping, I notice what looks like a small pipe plug on the side of the stuffing box (circled in yellow in the attached photo). Its appearance made me wonder if its purpose is to bleed air from the stern tube hose after going back in the water and before motoring.
Any thoughts on the purpose of this plug. And, too, what about the Phillips head screw just above it?

While discussing the procedure with my buddy who'll be helping, I notice what looks like a small pipe plug on the side of the stuffing box (circled in yellow in the attached photo). Its appearance made me wonder if its purpose is to bleed air from the stern tube hose after going back in the water and before motoring.
Any thoughts on the purpose of this plug. And, too, what about the Phillips head screw just above it?
