Possible Blown Coolant Seals From Overheat, Mixed Symptoms...HELP
 

I'm headed to formula drift in Atlanta (2 hours away) and I stop at a gas station with the car idling at 87*C. Upon leaving 5 mins later I get in the car and notice the water temp has shot up to 130*C and that the overflow valve in the coolant tank has taken a piss all over the parking lot. Car is immediately cut off. In an attempt to come up with a quick fix to get me to formula drift and then back home, I thought it could be the thermostat sticking so I took off the housing, removed the thermostat, and cut off the valve spring part so it would just flow open at all times, and added topped off the coolant. This did not help.

So I limp to formula drift 5 miles away at roughly 100*C and park and let it cool off over 6 hours. I started it several times and each time it wanted to bog out on the start, I had to work the throttle on ignition to get it to fire and idle right, and it was burning white smoke out of the exhaust upon start. However when idling there it sat at 85 degrees and seemed to be fine and the smoke went away. So we get halfway home (50 miles) and the car has ran fine, then BAM temp skyrockets right to 130*C, we pull off first exit and find its pissed the parking lot again and the temp isn't going down. I arrived home in a wrecker 4 painful and expensive hours later.

From everything I've read it seemed that I had overheated due to a cooling system failure and the blew my water seals as a result of that. However I've had some strange results in testing the last few days.

Thermostat replaced the next day. Then same problem on start up, lots of white smoke and temp skyrocketing (see attached youtube video). I kept smelling exhaust and got no 'sweet' as described. Then yesterday I flushed the entire coolant system and refilled it as specified on here. Turn the key car fires just fine, no hesitation, no smoke. Levels off at 85*C and wants to idle there consistently and stays even as i drove through the neighborhood.

SO question is...why did this happen? Any chance I may have dodged the rebuild bullet here? Is there a reason an overheat would cause a bog and smoke on start-up, but not have killed the seals? New to the rotary here, but learning at high speed...I'd just like some input and understanding before I can accept that I'm ok here...

I would say that you probably got some air in the lines, which is indictive of a coolant seal failure as exhaust will get in the coolant.

Or, you had a failing thermostat and you have since repaired that and swapped out your coolant removing any air that may have got in the system.

The only question is, will it do it again? Perhaps, perhaps not. i've had issues where my 7 would just smoke horrendously then i'd flush out the coolant and it was good.

Seals are gone. Still try to figure out why it originally overheated. Either way its rebuild time.

These were my exact symptoms and i'm now in the process of replacing my engine.

Are you also having to constently top off your coolant? That's another sign

I've only driven it around the neighborhood since having replaced the coolant so I'm not sure if it is actively consuming coolant. Don't want to get too far from home and it overheat like that again and risk damaging anything more internally and increasing the rebuild cost. Am going to try the champagne test today as well as run and check for coolant loss...and continue to plan this inevitable rebuild

I'm going throught the exact same thing. Consistently filling water into the system as if it's evaporating out. I flushed the system as well because of overheating issues last week. Mine doesn't smoke unless given some gas. I was/am hoping it's a tuning issued because I went single and haven't tuned the ecu yet.

Çoolant seal failed. Don't wait too long to have it addressed. It can corrode the sael grooves on the iron and make it unusable...and the inevitable rebuild that much more expensive.

How many miles on that motor. .
Mine would smoke at idle, and when I stopped at red lights, went away when I was moving...
temp was always good
Just rebuilt mine, coolant seals were shot, all cracked up and split

Hate to say it but it sounds like you lost a coolant seal. If you already changed the thermostat, the water pump is working, and you don't have a blockage its got to be the coolant seal.

Sounds like a typical coolant seal failure. How many miles on the engine?