just wondering the effects of running no thermostat on an FC. My co-workers and I are trying to think of any adverse effects it could have but can't think of any. We might try it on my TII and see what happens. Anyone might know?

Good or bad?

We're replacing my clutch with an Exedy 3 puck plate as we speak, so while we have everything torn down and hands dirty, just want to try it out.

Kevin

 

Your water wont stay in the radiator long enough to cool at highway speeds.

Jarrett

 

why exactly would you want to?

 

Without the thermostat, the engine will be more prone to overheating and having hot spots.

The thermostat does more than just opening up the coolant when warm, it also acts as a restrictor to flow so the coolant does not flow too fast through the motor.

If your buddies convince you that without a thermo is the route you want to try (for whatever lame reason), at very least use a thermostat with the crown cut off, so that the restriction will slow the flow down enough to partially cool the engine.

 

Agreed. Summit Racing even sells restrictor plates to replace a thermostat for racing applications. All they are are a round piece of sheet metal with a hole in the middle though.
You could easily make one yourself.

 

i am actually running no thermostat right now...Have been for about 2 months...i daily drive my car 120 miles..has no real adverse affects other than it doesnt boost as well because it doesnt get much over the cold mark even being ran at 65-75mph. I have a new one ready to put in but havent had time to do it yet. by the way this is in an 88 T2 with 112k and 90's all the way across on compression....It might be good in the summertime for racing but not for anything else

 

Oh and its not out because i wanted it out.....it was taken out when i had my lower intake manifold coolant seals replaced because the original was shot

 

HMMm aren't you the one with a seized motor???

Running without the thermostat will cause damage, the fools that drive without one are just playing the odds on what day a water seal blows or housing warps.

 

Some road race and open road challenges like the Silver state Classic and the Big Bend Classic use restrictors instead of the thermostat. I'm sure it has to be a specific size, and not just some random hole size. The dirt circle guys in West TX also use no thermostat in their cars........Yes they're rotary.

 

No no seized motor here. I drive my car daily...kinda have to now that my blazer is in the body shop....And if the motor does pop i have a 35k mileage motor sitting in my shed if the worst happens

 

no thats me and i found out why..... im gonna take pics for you guys tomarrow... lets just say that the plate with the 6 bolts..... was warped 6mm and was BLACK.... and the torrington bearings... lets not talk about those lol

 

If you run without a thermostat the cooling system has no way of regulating coolant temp at the optimum point. At low load the engine will run too cool because it's always being cooled to the radiators maximum capability, despite the engine's low heat output. The ECU will be overfuelling the engine because it thinks it's cold, resulting in less power and increased fuel consumption and engine wear. At high load the unrestricted coolant will be moving too fast through the engine to be able to absorb the heat the engine is generating so it will overheat. Basically there's no good reason to run without a thermostat. The cooling system is designed around a working thermostat, and only if it's stuck open or closed will it cause a problem. In that case a new one should be bought from Mazda (and nowhere else). A properly functioning thermostat does not cause overheating.

 

i run with out a stat in the summer all the time just lett it warm up first and make sure you arnt cavitating the coolent to bad if you are having problems with over heating this wont solve it if you just want your car to runn a bit cool for some blvd cruzzing then have at it