I just changed the thermastat in my Mom's car . It was stuck in the open position and I belive her car was overcooling .....She did not drive it very long like this , but ; I was curious as to what are the effects of over cooling ? Thanx guys .

 

Carbon buildup, and lack of gas mileage due to the car staying in closed loop.


BTW...open thermostats causing overcooling=a myth. Water doesn't have as much time to cool down as it goes through the radiator.

 

Ovrclck350 I thought that was open loop??

Over cooling won't matter, once the O2 sensor gets warm and starts sending a signal you don't need to worry, and in the summer it's not a problem.

 

maybe it's because you're in Texas. it's not a myth for those of us in colder climate states. i've seen it happen. winter time, t-stat was stuck open. takes too long to heat up. @ 35 mph, temp gauge starts heading down south. no heat, then Check Engine light comes on. had to stop to bring the temp back up.

 

You're right on the Open vs. Closed...my bad, I was tired.

BUT by overcooling you will have carbon buildup. OPTIMUM temperature for perfect combusion is 220 IIRC. You normally run cooler for power increases due to it helps cooling incoming air too, but you still have problems with carbon buildup.

 

Overcooling will cause premature engine wear. The oil never reaches operating temparature and the condensation caused by the normal heating and cooling of the engine never burns off. The oil gets sludged up, carbon buildup is greatly accelerated. The effects of overcooling are similar to what happens when you make a lot of short trips in cold weather. Oil doesn't do it's job until it's at 200 degrees or so.

Eric

 

Hey Eric , what does your S-10 run in the 1/4 ? . My Uncle bought an 89 S-10 he is about to drop a 350 in and race it .

Thanx for all the info guys .

 

Yep condensation is a big problem in the exhaust, if you don't have hot exhaust your pipes rust out faster.

 

I doubt they would sell 180 degree thermosats for production cars if there was a problem with carbon build up but maybe up north it's a big problem and you guys can worry about perfect combustion, I'll stick with keeping the temp close to the 195 degree stock thermosat and get the best of many worlds.