The brake breather has a leak in the 4620. The flexible tube that comes out of the top of the master cylinder and goes down, much like the old crankcase breathers. I guess they have to be rebuilt. Any advice on what / not to do?
There is no atmospheric vent there, it joins the plastic “drain line” from the sealing area of the main hydraulic pump and ultimately spills into the rear case.
There is a bleed line (small tube) that ‘tees’ into the gearbox … the plastic hyd. the pump purge line goes to the same ‘T’.