The invention relates to a cylinder valve assembly (19) comprising a pneumatic valve spring arrangement (25) including a first (29) and a second (31) valve spring member defining a valve spring cavity (33), and a valve spring venting arrangement (27) comprising a first venting cavity portion (37) in fluid flow connection with the valve spring cavity (33); a second venting cavity portion (39); a movable sealing member (41) arranged to allow a pressure difference between the first venting cavity portion (37) and the second venting cavity portion (39); a feedback channel fluid flow connecting the first venting cavity portion (37) and the second venting cavity portion (39); and a venting channel (53). The sealing member (41) is configured to be movable between a first sealing member position where the sealing member (41) prevents fluid flow from the first venting cavity portion (37) through the venting channel (53); and a second sealing member position where the sealing member (41) allows fluid flow from the first venting cavity portion (37) through the venting channel (53). The valve spring venting arrangement (27) further comprises an elastic member (55) urging the sealing member (41) towards the first sealing member position.