Cons of running an open (stuck) t-stat?

[Ross-N-Chicago]

My stat is stuck open, I'm pretty sure. Will this just cause a rich condition for now until I swap in the new one?

 

[A Wise Guy]

I don't know about rich but I do see a cardboard grill thermostat in your near future. Well maybe not Tuesday or Wednesday.

 

[TheJMan]

I ran a stuck open thermostat on my old 1993 for over 2 years. Didn't seem to hurt anything. Maybe a distant possibility is premature catalytic converter degradation due to the extra fuel in the mixture. Other than that you would just use extra fuel due to the low coolant temperature.

 

[Ross-N-Chicago]

Wise Guy, just looked at the wweather. Thanks for making my nuts shrivel even before it gets cold here. At 32, I feel like an old man waiting for Spring already.

 

[CDW6212R]

Buy a new 180, they aren't expensive, unless you choose the Motorad(Failsafe) version. They are the makers of the thermostats that will fail open, and not closed.
There is an O-ring on the early Explorers, I like that better than a gasket.
Don

 

[Glacier991]

failed open will slightly accelerate engine wear (slightly) and cost you some in efficiency.. might actually improve peak peformance... you should still get into closed loop operation though


and I am a firm believer in a failsafe thermostat... I have the experience to prove the value of that.

 

[glfredrick]

I'm not sure about any increased performance with lower temps in the engine with our Fords... I know that lowering the temps is a generally accepted hot rod trick - and it can help with detonation issues, but when I tried lowering the temp on my Ranger 2.9 it ran like crap.

I went back to a high flow stock temp setting and the performance increased from the lower temp one.

I haven't tried the same on the 4.0's but I'm reasonably sure that the same thing would occur seeing as how the Ford comupter is set up in a similar way.

 

['96explorereddiebauer]

An open stat can cause the PCM to think the engine is cold, which leads to a rich running condition. So that manes you will get less gas mileage and things in the engine may gunk up faster and the cat may wear out faster.

When you get a new stat, don't go anything lower than 195 degrees. Anything lower will, again, cause the PCM to think the engine is cold, making a rich condition, which leads to the aforementioned conditions.

 

[Eneurb]

The amount of extra fuel that you'll burn running in open loop all the time is going to cost far more than replacing the thermostat.

 

[BuffaloXplorer]

Correct me if i'm wrong, but won't a lower-temp thermostat also affect the actual heater temp? With the coolant not allowed to heat up as much, the interior heater may not feel as warm as well.

 

[Positive Vibes]

Not sure about engine wear but mine stuck open in Idaho during the winter and the truck would never warm up and the heater just blew cold air.

 

[glfredrick]

Correct me if i'm wrong, but won't a lower-temp thermostat also affect the actual heater temp? With the coolant not allowed to heat up as much, the interior heater may not feel as warm as well.

Yup...

There is one more disadvantage - and that is that your engine gets hot and cold spots becasue the water isn't regulated for flow or temp. This can actually cause head problems later on down the road. Unless it is a pure race car I recommend a good working thermostat and one set to factory temps (195F).

 

[A Wise Guy]

Wise Guy, just looked at the wweather. Thanks for making my nuts shrivel even before it gets cold here. At 32, I feel like an old man waiting for Spring already.

Hey, what's that lump in your throat? Oh, forget it.

 

[Ross-N-Chicago]

Awwwwwwww sheeeeeeeeeeeeeeeet