Accidentally posted this in the for sale section yesterday, I'm not really sure how that happened...I don't really plan on doing this, but I have read a few threads regarding Soobs without thermostats or their owner's taking them out. What are the negatives of this? Correct me if I am wrong, but it seems that all the thermostat does is prevent coolant from entering the engine block until it is at operating temp. I don't see that being an issue unless it was winter time when it would take forever to heat up and you may not get heat from the heater core as well. Otherwise, I really don't see a need for one with as much of a pain they are. On the other hand, why would it be there if it was not necessary ?

there's no reason to remove one, it doesn't "gain" you anything. replace it with a Subaru unit once or two in the lifetime of the vehicle and you won't have issues.

 

engines are designed to run at a certain temperature, tstats keep them running there. the ECU uses different routines for controlling an engine when cold or warm. without a tstat you may be running as if it's always cold, which means it'll run rich, causing bad gas mileage and maybe some long term effects to running rich as well.

 

view your engine as a more technologically advanced piece of machinery (even though it's just an EA ) than your lawn mower. they are rather designed, engineered, technologically advanced equipment in terms of thermodynamics, materials, etc.

 

i'll let others more knowledgeable say whether it matters or not in the long term.

Engines are designed to run at specific temps - the steel and aluminium are machined to precise tollerances and engineers have given a lot of thought to thermal expansion rates, etc. Most engine wear occurs durring cold running (startup) because the parts don't fit precisely till they reach their normal operating temp. If you run the engine cold all the time you will cause accelerated wear - in the short term its not a big deal - often folks run with gutted thermostats to prevent overheating in the case of mild head gasket failure. But it's not a permanent solution and it should not be done for nore than a few thousand miles.

 

GD