Echo LS21 Owners Manual v.1 - Manual (Page 33)

Fig. 27 Cylinder to be moved into mounting position
Fig. 28 Cylinder to be moved into mounting position
Fig. 29 Cylinder cradle reinstalled into mounting position
27. Carefully slide cylinder until completely into the
mounting location as shown in Fig 27 & 28.
28. Replace the cylinder cradle as shown in Fig. 29 & 30.