Hampton Bay or Liberty Garden model 708 wall mount steel garden hose reel elbow connector is made of aluminum which will deteriorate and leak.
The elbow connector can be replaced using the following parts that should be commonly available. The parts will need to be assembled in the following order of the direction of the flow of water.
½? brass 90 elbow ½? brass 90 street elbow ½? brass close nipple ½? brass 45 street elbow ½? brass FIP X garden hose adapter