driving without thermostat

[grasshopper]

Hi all. Is it ok to run your car without a thermostat if you only drive the car in summer ? What are the pro's and con's ?

[AriK]

These cars are finicky when it comes to cooling. It's best to keep thermostat intact in order to maintain optimim fluid transfer & avoid overheating. My opinion.

[TX82FIAT]

Interesting question, what effect would eliminating the warm up loop have at start up. Well, your car would in theory take longer to warm up and I suspect that would increase internal engine wear. Once our cars reach temperature they tend to stay at temp so opening and closing of the thermostat to regulate temp should not be as big an issue. It is better to have the car warm up quickly to where it runs better, uses the right amount of gas and has better emissions given the tune. I'd also be concerned with possible "hot spots" creating stress on the system the FIAT folks designed.

In theory, you could run the car without the thermostat loop. I don't think I'd do.

[81SPIDERMATT]

i ran with a thermostat that was stuck open for a while ... sorta the same as not having one I guess .... car did take a lot longer to warm up .. reaching operating temp as soon as possible is a good thing (quote from brad) .... once warmed up if I was in stop and go traffic the car would push that red line quick .... fan would help keep it off the red line most of the time but not any where near where it should be .... as soon as I was moving again temp would drop quickly .... now this was with all stock stuff when I first purchased the car .... pretty sure that my radiator was close to end of life and bad grounds made my fan spin slowly ..... hottest part of the day driving was just not done .... a well maintained cooling system I am sure would not be as bad as mine was .... I know this from reading several post about the subject and knowing guys with stock setups.... it was not long before I went aftermarket aluminum radiator with bigger fan and block flush and cleaning before all new fluids and new stat .... car now heats up pretty quick and never hits 200 ever .... running without a thermostat was and "old trick" from long ago in the summer months for a failing cooling system ...or a southern thing where it never gets below 45 degrees ... either way I think it is an old wives tale .... if running without it seems to make it better than you might have issues that should be addressed in the near future

[zachmac]

And, in what car? Is this a carbureted or FI car? I FI, definitely a bad idea as the FI uses that temp sensor in the T and you want to get to normal running temp as soon as possible. That said, even if carbureted still a good idea to run one for all of the same reasons stated above. Optimal situation is running at design temperature.

[So Cal Mark]

running at speed without a t-stat can cause the engine to run hotter as the water can pass through the radiator quicker, not allowing enough time for heat transfer.

[grasshopper]

Thanks. I am running a thermostat but just wanted the pro's and cons,,,thanks again.