Check the following:
Debris in the cylinder
The cylinder cap could be too loose
Incorrect pinning of the cylinder
The cylinder plug is not returned to the neutral position with the cylinder s...
The rim cylinder with thumbturn, XB11-979 (Figure 1) was designed to be installed on the inside head of the Von Duprin 98/99–2 double cylinder exit devices, see Figure 1. The rim cylinder with...