Where is the thermosat located on the motor ?

For the 3.0 ohv engine follow the upper hose the the housing on the intake manifold. It will be behind that housing. On the 3.0 DOHC engine. Follow the lower hose to the water outlet housing. The thermostat will be behind that housing.

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Smoking where.? tail pipe end.?
over heats, when, moving at 60mph
or only stopped.?
if that smoke is during a hot running motor, and is steam
the head gasket blew (or worse)
oil smoke burnt lingers a long time, steam goes away fast like tea pot.
smoke smells like burned oil, steam smells disgusting sweet due to
the coolant is 1/2 Glycol.
over heating has many reasons.
only stopped?, bad rad, bad pump, bad stat, bad fan clutch.(or elect fan)
fails to over heat moving, usually is bad fan (action)
steam at tail is coolant burning.

The thermostat is located at the top of motor where top radiator hose is it is not just the thermostat it is also the housing it comes as one unit. Not an expensive part and easy to replace just two bolts.

follow the top radiator hose to the block it is located in the housing at the end of the hose.

Follow the top radiater hose to the engine and the part it clamps to is the thermosat housing.The thermosat is in that housing.

CHECK THE HIGHT OF THE HEATER MATRIX IN THE CAB , IF ITS HIGHER THAN THE FILLER/EXPANSION TANK. THEN ITS AN AIR LOCK, LOOK FOR THE HIGHEST PIPE AND SEE IF THERE IS A BLEED VALVE, IF NOT TAKE BOTH PIPES OFF THE MATRIX FEEDS AND FLUSH OUT TO SEE IF IT IS BLOCKED, AND RECONNECT LOWEST PIPE FIRST AND FILL SYSTYM TILL WATER APPEAR FROM TOP AND RECONNECT RUN MOTOR, AND KEEP TOPIN UP

Folloe the top radiater hose to the thermosat housing,the thermostat is in that housing.

check the thermosat

Locate thehose on the left side of the car next to the air filter, trace this hose to where it enters the motor. Loosen the two bolts hlding the thermostat, place a mark on top of the thermostat before removing to ensure you replace it in the same manner in which it was removed. Take the thermostat place the thermostat in some water and boil the warter, if the thermostat opens, then check the temp sending unit located next to the thermostat.

Easy, simply trace the bottom radiator hose (lower left of the radiator) from it's connection point on the radiator to it's connection point on the engine, that's where the thermostat is located.