sounds like head gasket has blown
The thermostat on a Peugeot 307 is located on top of the engine, under the upper radiator hose. It restricts the flow of coolant based on its temperature.
Check fluid level WHEN IT cools off.
The lower radiator hose is located at the bottom of the radiator.
The thermostat on a Peuget 206 is located on top of the engine, under the upper radiator hose. It controls the flow of coolant out of the engine.
In most cases the lower radiator hose feeds the water pump. The upper radiator hose feeds the radiator.
Look on top of the radiator and follow the hose from the radiator to the thermostat housing. Look on the bottom of the radiator and follow the hose up to bottom of the block.
a hose clamp
Look on top of the radiator and follow the hose from the radiator to the thermostat housing. Look on the bottom of the radiator and follow the hose up to bottom of the block.
drain the radiator down below the top hose and unhook the hose from the radiator and the engine and pull the hose off.
The lower radiator hose supplies the water pump. The upper radiator hose supplies the radiator.
Upper is hose connected to top of radiator, lower is hose connected to bottom of radiator.
Follow the top hose from the radiator that goes to the engine, the first thing the hose connects to next to the engine is the thermostat housing, two bolts take them off and wala! there is the thermostat.