My car get hot easily we have replaced the thermostat and fans. when under the hood; the radiator hose get hot and expands because of pressure. when you take the cap off the radiator water explodes everywhere. What could be causing this pressure????

 

Umm natural steam.... that's far from safe if you think hot coolant spray doesn't hurt try getting it in your eyes or face it's oily and burns. The hose is supposed to be firm not expand post a pic, but i'd be willing to bet excessive air bleed the system(google).

 

the car doesn't even get hot. the hose just gets really pressurized. I've read about bleeding the system also read that it could be a radiator cap or the water pump or the head gasket.

 

My money is on combustion gasses getting into the cooling system, head gasket, sorry dude... That'll pressurize the system real quick if it's bad enough.

 

Replace the hose if its expanding and properly bleed the system.

 

This. If your car is not overheating but the system is exceeding the radiator cap relief pressure then you're getting combustion gases in your cooling system.

 

Again the hosses will expand when there old, doesnt mean the head gasket is blown!!!!

When the hose gets old and exposed to heat it will tear through its threaded lining and the rubber will thin out and expand! this is when you need to replace your hose! a good hose will not expand from exssesive heat or combustion gasses entering the coolant.

Also when the engine is hot and running removing the radiator cap will cause hoot coolant to burst through!

DO NOT REMOVE THE CAP WHILE THE ENGINE IS HOT!.

If the engine is cold you can start the engine and bleed the air out the coolant with the cap off untill its topped off and free of air then you can put the cap off but do not take it off after or it will cause coolant to fly out and burn your face.