System application of a sealant plug

A system for applying a sealant plug for applying a sealant plug (30) through coaxial unaaguja (14), the application system comprising: a support structure (36, 36a, 80); and it caracterizaado that it further comprises a plunger (38) configured to be received within the coaxial needle (14) and is movable relative to the support structure (36, 36a, 80), the plunger (38) being configured, also to push the sealing plug (30) through the coaxial needle (14); graduates markers (52) configured to align the plunger (38) in a desired position relative wing support structure (36, 36a, 80); and a locking mechanism (40; 48; 85) configured to lock the plunger (38) in the desired position conrelacion to the support structure (36, 36a, 80).