Bauer Magnum SM 540 Operating Manual page 21

Moisten the thread with Loctite
Spray the O–ring with lubricant inside
When mounting the rotating collar ensure that bolt and groove are properly
aligned (misalignment will bend the pin when force is applied and the spring is
pressed away ensuing excessive pretension of the sliding faces).
Press on the mechanical seal with the help of the sleeve (remove the sleeve
again).
Insert the disk.
Mounting the collar
The disk must be positioned in such a way that the threaded bolts are accessible
through the slot.
17
Operating manual for BAUER gear pump