Yep - Easy_E1's post covers why the old "Remove the thermostat in the summer" tradition never really accomplished much.

What you learned from your testers is certainly good, and proves the real-world worth. Kind of like traditional knowledge vs science - which is credible always depends on the skill of the source.

There should be an SAE standard or RP on what I described...been 30 years since I did it myself, and I don't quite remember. The benefit of doing that kind of test is you can then advertise "xx% more cooling than stock."

Ken

 

something i meant o check on some time ago and never did=

is our stock Tstat a fail close or a fail open? i heard once it may be a fail open and never got a round to checking

 

Well, seeing as how it is sprung closed, I'd assume it was a fail shut.

 

I think you might want to try the AccessPORT from MM, cuz u can adjust Fan On speed to ANY temp you want.

 

I've never even come close to overheating in an autox (stock radiator, stock fans, stock waterpump), and I put up top 10 times, 90 degrees, 100 degrees ambient, doesn't matter. If your coolant is boiling then something is seriously wrong.

Were your fans on? If not, then its a relay or fuse problem.

If your fans were on full blast, then its likely a thermostat problem.

Now would be a good time to buy some vacuum tube and reroute the coolant exit port to the passanger side of the oilpan. Or else the engine bay is going to get messy

 

If the thermostat is sticking closed, then its something that you need to fix immediately!

 

^ again +1 ... don't know why everyone is recommending this guy should buy all kinds of parts/upgrades for this problem. It is NOT normal for A car, HIS car, or ANY car to boil over in this situation. Anyway NM isn't like 120 deg right now, it's barely warm there, and humidity or not, this is abnormal car behavior.

There is something else wrong, it should be determined WHAT, and taken care of BEFORE any mods are done.

 

you guys are probably right. I didnt hear the fans kicking on very much but i made several mistakes while autocrossing.

1st gear throughout the entire day.
didn't turn on air or move **** to hot position.
continuously shutdown car throughout day.


after letting the engine cool down, refilling coolant and checking all other fluids. i have not had another problem with overheating and water temp is within normal range again.

the only maintenance done the previous day was the msp16 pcm reflash. not sure that would effect it?

I think ill take it to the dealer and tell them it overheated while in stop and go traffic.

 

Excellent! Do you mind telling us what gauge is telling you this?

 

sadly i only have the stock water gauge in the car. I know it sucks but when the engine runs normally it is just below 1/2. when it over heated it was just before 3/4. I caught it right as it started steaming slightly. I don't think i did any engine damage and everything seems to be ok but i am concerned about it.

 

Sorry to be so critical, but its probably better if I'm super harsh now and we save your car.

I've seen temps of 240-250 farenheit and the stock gauge will not move.

If it was in 3/4 of the way I'm assuming it was above that.

 

yeah that sux!!


well what do you recommend?

 

Take it to the dealership, complain of boilover at slow speeds. Tell them you think its the thermostat.

 

k thanks alot!!

 

If it's the garden variety design, it can fail either way, depending on what breaks.

Several years ago I had the thermostat on my Accord fail both ways. The car was not warming up, so the thermostat was clearly sticking open. Ordered a new stat and top hose (no point putting an old one back on). On the way home from the dealer, the stat stuck closed. Made it home in five minute segments, many cooling stops along the way.

I forget the exact details, but it jammed open because something failed and got stuck. Eventually the piece that it was stuck on failed, letting it shut.

Ken

 

I think you may have been spot-on with the idea that the cap might have been loose.

 

It could be just a thermostat problem thats true.

Yes he can track it without upgrading anything, but if he tracks his car a lot and want his car to live longer, then he will 100% need the parts that people have mentioned in this thread.

Hell my car never overheated, but I still want the best for my car.

 

you guys were pretty close. All is fixed yeaaahhh!!!

the damn stock radiator cap refused to hold a good pressure and and had a bad seal. the new cap is a japanese cap unlike the american one and everything is running much better. the engine bay no longer feels like i can fry an egg on it but is cool to the touch. ya!!

 

Not "you guys" but THIS guy. Good diagnosis, Spin.

 

Thanks, I learned that the particular solution the hard way...one day I didn't quite tighten the radiator cap at a track session....took me a while to figure it out....but...I won't forget soon...

 

my bad, congrats Spin9k!!
ill buy!!

 

BAD NEWS guys

after mazda tested the radiator with pressure tests and replaced the cap that was losing pressure, they said everything was fine and fixed. After about a week when it started to get warmer, roughly 75 degrees, I put the AC on max and was driving in stop and go traffic. I noticed a weird smell from the AC and turned it off. A few miles later I heard a whirling sound, immediately started to look at my gauges and noticed the water temp. was at 3/4 the way again and my engine was overheating. I then turned my heater on full blast to get the temp down and was able to get it to the dealership. I am so sick of this problem. I think it might be that my fans are not turning on. any ideas?

 

ok, from your description, i'll give it shot at analizing this.

depending on the "whirring" sound, it can be a possible fan/motor damage. the dealer may have just been lazy to check the overall condition of the car... sad but possible. afterall, the fans are tucked away far down... and ANYTHING that falls in can easily jam up the motor/fan from turning due to its diagonal mount design.

the radiator cap dilemma... well, that can just be a fail of the two which can also be affected i believe. and so the thermostat stuck open, fans don't come on, cap being the first to go...

thats my best analization. if the "whirring" sound is from the waterpump, you should overheat as well... but its tricky as it most likely will fail upon hard driving and the sound always be on, as it is a mechanically driven item...makes sense?

the reason why gauges are so important to me as a first mod, are from careful study and knowing the rotary runs HOT! and that there is a "window" in which the oem temp gauge will move again from middle position. this is NOT a good design in the dummy gauge. but what can be done? a rotary engine don't work like a piston car, and people can be tricked into thinking the car overheats every five minutes of driving... but it does generate a lot of heat, and it fluctuates quite quickly.

so, anyways. to make the story short. the dealer needs to cover their *** now when you bring it in for more repair. it should be covered free of charge, as you souldn't pay extra for their mis-diagnosis. if they deny you...well, when you overheat the next time, its gonna be on them to buy you a new motor!

what else can be changed? the cap is good. but thats not the source... it can be whats affected by the source, thats what i'm sayin. they should thoroughly check the cooling system next time around, and that should include a new thermostat, a fan switch, and... if i'm correct, new fans/motors.

hope i'm somewhere close by your description.
GL

troch

 

When water pumps fail, they go "clickety-click" in random way. Sounds like pennies in a clothes drier, only much more quiet.
When fans fail, they go "chuff-chuff-chuff".
Now, if the fan (or the relay/fuse) fail completely, you will hear nothing.
When the car was overheating, where the fans running? It should have been pretty obvious - they are really loud.

 

again thanks for the quick replies!!!


the fans don't sound like they are coming on at all. Every time i came to a stop and waited more than a minute the temp would go up. If i continued moving without stopping the temp would stabilize. the car only has 5000 miles on it so it should be covered by warranty, for now they gave me a rental.