Don
Junker outboard exhaustvalve.
I have looked through all my papers and cannot find any detail on the subject so I have to design the valve based on the photos available. Down below is my sketch which is an assumption/ partly shear guesswork.
The valve consist of a tube steelhousing going through the pressurehull ending in an outboard valve which connect the muffler ( sea) and the inlet ports of the Junker opposed piston dieselpart. The valve has a free rotating valvedisc (red) and stem with a bore for the valve spindle ( yellow) on which the disc is free to rotate.
The other end of the valvespindle (yellow) has a threaded end engaging threads in the valve wheel hub (pink) which is kept in position by a rim disc in the housing. When turning the pink valvewheel the yellow valvespindle moves up and down shutting/opening the valve, the pink valve hub stays in place. As the red valvestem and disc is connected to the yellow spindle they follow the axial movement of the yellow valvespindle. At the other end of the red valve stem is a gearwheel having a hub with inside slots engaging similar slots on the red valve stem, the gearwheel is kept in place by the housing. Thus the valvestem is sliding axially in the gearwheel when the stem is axially moving by the handwheel turning.
When the valve is shut and the sternbuoyancy tank vent is open, the Junker valve is locked by the interlock (violet) as a small cam keeps the red valvestem down (shut).
If you have to grind the valve, you shut the valve, a small shaft end protrude out of the casing as shown, and a bar is secured by a screw on this shaft and you turn same thereby rotating a worm which is engaged to the gearwheel on the red valvestem. As the gearwheel bore has slots engaging matcing slots in the red valvestem, the valvestem and valve rotates around the yellow valve spindle and you are grinding the discseat against the housing seats. The valve opens towards the seapressure and you cannot open the valve unless the sternbuoyancy tank vent is shut.
An airpipe (green)is connected to the outboard valve housing which makes it possible to blow the exhaustpipe to the sea while the exhaustpipe is shut to the Junker cleaning the exhaustpipe for water prior to opening of the valve.
I should assume it is an additional hull exhaustvalve as usual. PHU!! Confusing? read it once more and look at the sketch
Tore