The radiator hose which I assume you mean although you write rad, is connected to the radiator. One on the top of the radiator and one on the bottom. the one on the top
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I can think of Three things,1. Thremostat stuck open.2. Poor quality radiator hose or the spring inside is bent or missing.3. Low water level in radiator.Good Luck
On my 4.0 L OHV engine the top rad hose gets hot when the thermostat opens ,
and the bottom hose from the radiator returning to the water pump is much cooler
because of the heat given off by the...