Furuno radar antenna removal

[Pete]

Have a 41 inch open array Furuno radar antenna that is fully operational. This is an older model with a white case antenna and a blue flat face with white "FURUNO" lettering. The blue face is faded and the white lettering is all but disappeared. Time for a refreshed look. I attempted to remove the antenna by removing the four machine screws that attach it to the rotating base. But the flange on the bottom of the antenna and the rotating base are as tightly bound as when the screws were installed. I have tried reasonable pressure but no movement. Before I go further I could use some expert advise on what works without damaging the unit.

I would appreciate input on how to proceed.

Thanks

Pete

 

[Boatsb]

It bolts down to the waveguide and has a sealant.

By the way you can not paint the radiating surface.