We own a 1996 sable and recentlymy father and I replaced the original engine with a 63,000mi motor. (V6 Vulcan engine just like the original motor)The new motor runs fine, however, the temp gauge never gets a needles width above the "C". Even after driving the car on the interstate over 70MPH for an hour, the car never gets hot according to the temp gauge. I recently tried to use the heater and found that the heater will not produce any hot air.


The replacement motor had a brand new water pump and thermostat installed on it so I dont think its either one of those. My knowledge lies with BMW"s so I'm not familiar with the Ford / Mercury built cars. The repair manual we have is worthless and I'm not sure where to start.


It would seems as though the car should have heated to proper temp after several minutes of interstate driving but according to the gauge it didnt. Even if the temp gauge is faulty and the car is running at normal temp shouldnt the heater work, regardless of what the temp gauge says ??

 

well this is just a guess....while the engine that you put in was not being used, the "new" thermastat may hve dried out and be stuck in an open position..if this were the case then the coolant would always circulate and not warm up...also low coolant could cause this problem...since a thermastat is cheap you should start with that...have you felt the hoses after you have warmed the car up...feel the radiator hoses as well as both heater hoses..be very careful as the hoses and exhaust will be very hot

 

more than likely its a Thermostat. Generally no heat regardless of "brand" (Ford, General Motors, or any make) if the thermo is stuck open as frankin*** mentioned not allowing it to warm. Also, check the required thermo for your engine. Make sure its the correct one. Different Thermos for different V6's even - not sure but think 185 is standard on the vulcan V6.


Someone more familiar with the themo temps correct me on the temperature ratings. Some use a 195 degree I think.