I just put a new theromstat on after it was overheating, now the hose to the radiator look like it about to pop and I also flushed the radiator and added anit- freeze. And I don't have heat inside the truck... By the way its 2000 Mercury Mountaineer. Thanks

. Flush the heater core.

. Install a new radiator--passages in the current one are likely blocked with phosphate scale, due to not using distilled water. Antifreeze combines with minerals in the water to form scale.

. Refill with a 50/50 mixture of the proper antifreeze and distilled water. Alternatively, refill with the proper prediluted antifreeze. I suspect your Owner's Manual calls for Ford Premium Antifreeze with Bittering Agent (Green). Change coolant every 30,000 miles.

Overheating an aluminum head engine, even once, can warp the aluminum head, damage the valves, and blow the head gasket. Repairs can run $3,000+, so this problem needs to be solved quickly and properly. Have the truck towed, if necessary, for repairs.

IF the upper radiator hose is about to pop, that usually means your radiator is clogged. Hot coolant expands and comes out the top of the engine and into the radiator. If radiator is plugged, there's nowhere for the coolant to go.

I know this may sound funny but are you sure that you installed the thermostat correctly? If it was installed upside down it would not be able to open correctly causing the same problems as before u changed it.