front right brakes locked up. released after about 20mns. caliper or master cyl?

thanks. but there is a "proportioning valve" (i think thats what its called..) the brake line runs through right under the master cylinder that i guess splits up the front and rear. so that wouldnt be the problem either? definitely the caliper and hose?

The best way to go at this is to replace the caliper and flex hose, then bleed system!! 99.9 % of the time that will take care of it!.. Pretty good odds....