Thermostat

#1

I have a 1991 Dodge Dynsty, 3.3 engine. I’ve replaced three thermostats and a pressure cap. But the temperture will only come up to a 140. What’s wrong?

#2

How are you measuring the 140? and what temperature thermostat are you using? Is there a reason you believe there is a problem other than the 140? temperature?

#3

I agree with Mr. Meehan. How are you measuring the engine temperature, and what was the opening temperature of the thermostat you installed?

#4

My dad is using a heat gage on the hose by the thermostat and the thermostat is a 195. There are no other problems other than not enough heat coming though. It’s slow getting to the 140.

#5

Could you tell us more about that gauge? Is it a remote sensor? If the hose is being measured by a remote gauge, remember that the hose will insulate the coolant so you are only getting the outside of the hose temperature and not the coolant temperature. A reading off the radiator would be a lot more accurate. Has the gauge been checked for accuracy?

When you say it is slow getting to 140? is that at idle or while the car is being driven, and how long is it, and what is the outdoor temperature and are you idling the car or driving it and driving it at what speed, and is it different at say 35 mph vs 60 mph

Remember it is cold out and when cold it is going to take longer to reach operating temperature and it will take longer to warm the cabin due to the cold air from outside.  Cars vary on how well they heat.
#6

This sounds like a case of someone making a problem where none exists. There is a dash engine temperature gauge, isn’t there? What’s wrong with it? If it’s believed that it’s not accurate, you can get after-market temperature gauges from an auto parts store.