Magnetic fluid has many technical applications and many new ones are being developed. One of the applications is in magnetic fluid seals. This publication describes the new phenomenon of the magnetic fluid seal reseal
mechanism, discovered while carrying out research. This phenomenon is manifested by the pressure oscillation medium being sealed, which results from the instability (cyclic destruction and rebuild of the liquid ring) in the magnetic fluid seal. It occurs in an inhomogeneous magnetic field and, in this case, is caused by the eccentricity of the seal components. In order to study this mechanism, magnetic fluid characterized by different physical properties was selected. Numerical simulations were performed to determine the magnetic field distribution in the seal. Research results showed the possibility of measuring the eccentricity of the magnetic fluid seal elements. Studies have shown that it is possible to determine the displacement of about 0.01 mm.