ok got a oldsmobile cutlass im working on. THe guy says the thermostat keeps going up like it wonts to overheat but wen he turns the heat on no heat comes out the vents but the thermostat stops and stays where it is and wen he cuts off the car it starts leaking radiator fluid. would this be his radiator needs to be replaced or is there a leak in a hose and the thermostat needs to be replaced???

 

That's hard to say without seeing the car. The overheating could be fro a bad thermostat or even a bad radiator. The coolant overflowing could be from it boiling over as well and just be coming from the overflow.

What year is the car and what engine is in it?

 

remove the tstat= put cap back on (fill with coolant/water- & run-look 4 leak & overheating???????????????