We recently became poud owners of an 87 F700 with the famous lucas girling brakes system. The problem we are having is that when the brake pedal is applied the hydraulic pump for the break system locks up and the belt slips on the pulley. The brakes still work to some extent, probably not up to par. I am not very familiar with this system and was hoping that some of you fellows that have some knowledge of this system can give some advice.