Sounds like part of a heater hose. Sounds like part of a formed heater hose.
The thermostat CANNOT be repaired it has to be replaced. There should be a hose coming out of the top of the radiator hose going to the engine. Where it connects to the engine should be a housing with two bolts on it. Disconnect the hose and the bolts and the thermostat is behind the housing. You might have to move something out of the way to do this, but it is usually rather easy. Hope this helps.
In the thermostat housing. Follow the upper rad hose that should hook into the thermostat housing. It usually has 2 bolts holding the stat in place
The thermostat is on the top side of the engine. Follow the hose from the radiator to where it goes connects to the engine. The housing may have the coil bolted on to the outside, depending upon the model. On the top side of the housing is an Allen screw, which should help identify it, plus the temperature sensor is on it as well. The housing must be removed to change out the thermostat. The set screw must also be removed during refilling the system to allow air to escape.
it is either on the side of the head or on the thermostat housing
thermostat is located inside thermostat housing, this is where the top radiator hose connects to engine
It is under the housing where the upper radiator hose hooks to the engine.
Under the housing where the upper radiator hose hooks to the engine.
Under the housing at the engine end of the upper radiator hose.
Follow upper radiator hose to the engine, it is under that housing.
Under the housing where the upper radiator hose hooks to the engine.
It is under the plastic housing that the upper radiator hose hooks to on the engine.
It is under the housing where the upper radiator hose hooks to the engine.