A little history first. 2 years ago I was pulling my boat home after a trip to Lake fork. About half way home I noticed smoke coming from my tires so I pulled over to check the bearings. After trying to pull forward a little bit after I stopped the brakes were locked up. The only way to get them to release was to unscrew my brake hose out of the master cylinder to relieve the pressure. After that everything was good I really don�t need trailer brakes so never fixed it and haven�t had a problem in 2 yrs. Last week I took the boat out and notice when I was backing the trailer in to load the boat that the back tires were locked up. I got it backed in the water and loaded the boat. When pulling out I notices a grinding noise from the back wheels. What would cause the grinding noise if I don�t have the brake line hooked up to the master cylinder? Any help is appreciated.

A brake drum full of crud possibly.

Time for R&R of trailer brakes. Yes, you do need those brakes. In an emergency stop situation, it can help keep the trailer behind the vehicle.

I would look at a disc brake conversion. Much more reliable.

just get rid of the brakes and be done with it, I can see having brakes on a 10,000 lb offshore boat, but a glitter rocket should be fine