Its been pretty hot here in Indiana the last couple weeks and i noticed the temps a little higher than normal in my DD. The would go up to like 2/3s on the guage and then level off at 1/2. Went by mazda on my way home from work last night and picked up a new OEM thermostat. When i removed the old one it had quite a bit of build up on it and i think it was causing it to stick while opening. Removing the old gasket from the upper pipe was the hardest part, ended up sanding it off because it was so old and hard. Put it back together and let it idle for a while in the driveway and then took it out and beat on it for a little. My temps aren't getting above 1/4-1/3 on the guage now. I'm glad i noticed before thermo failed completely and overheated my motor. I don't have a question just a friendly reminder that everyone probably already knows.

 

I replaced mine pretty recently. Just be careful if you have an S5, the plastic Tstat cover is fragile as crap. I barely touched mine and it broke.

 

Replace something that says it should be replaced every 60,000 miles... uh huh.....

 

Well it only had 42k on it, and it was an OEM. Its such a cheap part that can cause a lot of damage, that its worth replacing early.

 

yeah replacing my thermostat a few months after i bought my car fixed all my cooling problems

REPLACE YOUR THERMOSTAT HOUSING BOLTS. They are brittle and easy to break when you tighten them.

 

yeah replacing the thermostat can help prevent or solve heating problems... especially if it's old or in bad condition

 

Thats what AntiSeize compound is for.

(or grease)

 

its a mazda, you change the filters and spark plugs periodically, but everything else is inspect (each service) and replace as needed.

 

or just get aftermarket gauges.. and have better monitoring

 

i have put 40k mi on my rebuild, and had to replace my NAPA oem replacement Tstat now 5 times.... i dont know why they keep bustin apart, sticking open... my problem is that my car is running too cold!

 

Its a good thing that its sticking open rather than sticking closed, If stuck closed you car will run too hot rather than too cold.

And after 5 times wouldnt most NORMAL people switch manufacturers? Or do you just like replacing them?

 

Or... do things the right way.

As for the thermostat, I think I remember it being 60,000, but... I could be off on the mileage.

 

I plan On changing mine every 30K, along with full cooling system servicing.

 

Not a bad idea considering they're pretty cheap.

 

Because you keep buying a piece of crap.

ONLY BUY THE MAZDA FACTORY THERMOSTAT.

Don't know why people just don't get that. Its only been posted here 1000 times.

 

how much do the t stats cost if i buy one from the mazda dealer i have to take my car there this monday to replace the auto seatbelts for FREE since the recall on them so i mise well pick one up if i got the money since i just broke 60k on my car and aint sure if it was ever replaced before

 

Thats not necesaraly true, I have only used autozone and advance auto thermostats, No troubles at all. However, I do not use the valucrap thermostats I use the midrange thermostat.

Ive never seen anywhere (exept here and at miata.net) that mazda parts are actually better than generic brands. If there was a mazda dealer near me, I might, Just might possibly use mazda brand stuff.

I might be willing to aggree that mazda parts last much longer, BUT If you perform preventitive maintanance generic parts are just fine (for my cheapass atleast).

 

It cost me ~$20 and comes with the gasket.

 

Countless threads on that.. countless.

The most common "warm running" issues are caused by using a supposedly cooler Stant (maker of most aftermarket thermostats sold in the USA) in a FC. Replace it with the correct Mazda brand thermostat and cooling issues disappear. Many many members often think like you, that an aftermarket thermostat is fine... well until they put in th correct OEM thermostat. Remember up until very recently Stant's thermostat for the FC actually was for an entirly different vehicle that happened to fit the FC (and I still have not confirmed in my actual hand that they have made a FC specifc thermostat).

See 99% of the aftermarket thermostats do not have the bypass and weep hole that the OEM thermostat does (and is really required on the rotary engine due to higher RPM and lower torque on the pump). So by using aftermarket thermostat, you:

#1 overload the water pump when cold and cause pump cavitation until the thermostat opens (which then allows air mixed with coolant from the cavitation to be run through the cooling system leading to:

#2 wrong temp cooling.

Mazda specs the factory thermostat to be opening around 180F. Yet with most aftermarket thermostats that claim fully open at 180F the cavitation caused by no weep and bypass, they actually run much higher.

Of course if you have a poor mixture or high phosphates count in the coolant mixture, the bubbles caused by cavitation tends to foam, creating a whole 'nother set of cooling issues. Remember air does not cool as well as water.

 

Japanese engineering from the company that made the car > aftermarket from an American company.

 

I replaced mine with the OEM thermostat and my temps dropped from 1/3 on the gauge to 1/4. Of course flushing the system helped a lot too.

Besides, I'd rather pay $20 and have the peace of mind than worry about replacing an aftermarket unit more frequently.

 

Exactly. I don't see why people don't go with the Mazda unit that's been proven time and time and time and time... again.

 

Everybody wants to be a cowboy.

 

Mazda OEm cracks open at 180 and is fully open by 200.

FYI. On my S4. Watching the stock unit vs my autometer unit.
1/2-3/4 on the guage can be anywhere between 200-235+

 

Am I the only one that caught this "it had quite a bit of build up on it" ? Flush your cooling system and use only distilled water.