fuel pumps running hot

[bigdaddy4x4]

ok I have been thru 3 different hi pressure electric fuel pumps my pump is not in the tank its mounted on frame rail in front of the fuel tank rt side about 4 inches from the exhaust pipe the first 2 fuel pumps failed after getting hot they were not brand names the 3rd pump is a walbro it has lasted the longest but in this hot weather in ga. it gets hot and will just shuts off let sit for a few mins. and it will start to working again can anybody tell me what causes the fuel pumps to stop running and when it cools off it works ??