cracked block or blown head gasket two most llikely ways. Neither is a cheap repair.
On my 2000 International with a Detroit series 60 engine the water temperature sensor is on the back of the engine, passenger side in the cylinder head. Gears
On the side of the engine block on bottom of the motor
It could be a freeze plug on the side of the engine block by the motor mount.
The water pump for an s-10 engine is located on the front of the motor. The engine can be damages if it overheats due to a bad pump.
the engine will shows overheat sign on the heat gauge
4.3 engine - front of motor above water pump
If the motor got water in it do not attempt to start it. The water needs to come out first. Water is very bad for your engine because it causes rust and doesn't allow the pistons and valves to move properly and all sorts of nonsense. Take it to a repair shop and have the engine disassembled and the water removed. How did the water get in there?
To change out a water pump in a Series 60 Detroit diesel, you need to locate the water pump in the engine. You need the right tools to remove all the fittings and take the pump out, them replace it with a new one. The owners manual has a list of all engine parts and diagrams.
Overheating the engine - usually by running low on water or a waterleak causing same thing.
it is on the drivers side of the engine compartment in the front of the motor when you start the motor you will see a small belt turnig and you will need a specail tool to get the water pump out
Water will easily damage bearing surfaces, as well as metal surfaces. Since water is hydraulic, it tears up a motor. If there is definite damage, the motor would need to be rebuilt. Cost: depending on what motor you have.
carries water from and to the engine to the radiator for cooling, there are 2 and contain hot water when the engine is running and will still be hot and pressurerised for an hour after the motor is shut off.