st1llet0

iTrader: (2)

Back info, about 2 months ago I blew a radiator hose, engine temp started to go up and I pulled over immediately. Replaced the hose, replaced the coolant, and started to drive home. It overheated so I checked the thermostat that was stuck closed. So I went a bought a new one from autozone, and because I was in a hurry, I took what they had in stock, and 196 degree thermostat rather than the 180 degree. It worked great for about 2 months. Last week me and a self proclaimed ricer buddy were playing around in the suburbs doing a little spirited driving, afterwords I noticed my engine temp would get really low. I checked that thermostat and it was stuck open... Ok, np. So I drove with a stuck open thermostat for a couple of days, taking it easy, (I had to choose between thermostat and dinner, I chose dinner) I bought a 180 degree thermostat Saturday and put it in no problem, I've just noticed that my car is reaching operating temperature like twice as fast, (1.25 miles at 40mph and 2500 rpm rather than 3 miles at the same) Is this normal? My guage reads "normal" but it is the stock guage so who knows what the actual temp is.

Car is '89 gtu 110k miles no mods.

Oh, and if it matters any, 4 days or so before the thermostat got stuck open I changed the oil and put in 20w50, I don't know if it matters or not, but yeah, pick it apart and see what your collective mind can come up with oh great forum....

RB_eater

iTrader: (1)

A thermostat that isn't stuck open will warm up a lot faster, seems obvious to me.

RETed

I dunno what you people are smoking, but the stock Mazda OEM thermostat is fully open at ~195F.


-Ted

st1llet0

iTrader: (2)

What I meant to say is, my car warms up faster now with a 180 degree thermostat than it did with a brand new and fully functional 195 degree thermostat. BTW, I bought a 180 because that's what the Haynes said was the stock, I know I should have consulted the FSM instead, but I wasn't at my pc.

jackhild59

iTrader: (7)

I don't know either, but if he keeps dicking around, he will be smokin' his engine.


st1llet0-

Nothing is ever normal if you have a non-stock thermostat. Quit worrying and screwing around with your cooling system. Normal is an OEM thermostat.

If you just get an OEM thermostat, you won't need the answer to your question.

SpooledupRacing

amen go oem or go home when it comes to the thermostats..

micah

Definately, autozone = teh suck for most stuff. My napa sells OEM t-stats... yay!

http://www.mazdatrix.com
http://www.atkinsrotary.com

17-20 bucks is more than autozones pseudo t-stats, but its less than an engine rebuild.

st1llet0

iTrader: (2)

Allow me to clarify, I'm not trying to "Improve" or modify my cooling system. I bought the car with a 180 degree thermostat in it. Thermostat stuck close, i bout 196 degree, thermostat stuck open, now with 180 degree thermostat engine reaches operating temperature 2x as fast as it did with a brand new 196 degree thermostat or with the functional 180. All I was asking is, under the driving conditions specified earlier, does it sound like I may have a problem.

BTW, I think someone would be more likely to toast thier engine by IGNORING out of the ordinary behavior rather than INVESTIGATING it.

I understand that most of the forum veterans here know thier stuff, and I'm not trying to disagree with you, but I think you may have misunderstood my concern.

micah

My concern is that you have an OEM t-stat before troubleshooting the rest of your cooling system.... But yes... you are absolutely correct. You are wise to know something is up.

st1llet0

iTrader: (2)

So when you say OEM, you mean Mazda brand thermostat? I got mine from NAPA for 11 or so, the only place that actually had one in. Like I said, according to the specifications listed in the Haynes manual, the thermostat meets OEM opening temperature guidlines, (I think the Haynes book said like 182 degrees) So is the worry that my NAPA stat isn't up to snuff? like not opening all the way or not opening at the right temp? Or is the haynes book wrong and I really should be using a 196 degree stat.

micah

Yeah, OEM = whatever came on the car. it won't say mazda on the t-stat itself, but it should on the box it comes in. It'll probably say NPK on it (I think thats the brand....)

jackhild59

iTrader: (7)

You are correct-It does sound like you have a problem. No one told you to ignore the problem. You have been told, repeatedly, what the problem is and how to solve it. I am sorry you don't like the answer. Just don't whine that you are misunderstood.

Your concern is apparent. Your cooling system is acting abnormally. You are now on your third failed aftermarket thermostat. Duh!? You investigated it by asking the experts on this forum. You got our very best answer. Go OEM. Period. If you did a search and spent the amount of time you are spending dicking with a t-stat that meets Haynes standards, you would know the following: The most likely reason you have abnormal function is the after market thermostat.

If you don't want to accept the answer, then get used to the abnormal function.

Maybe you could ask your ricer buddies what to do! Then your next ill-considered step would be to start replacing expensive parts, like the water pump, the radiator, the oem cooling fan.

Uh, you do have the stock cooling fan, don't you?

http://www.rx7.com/store/rx7/fcengine_cooling.html

Don't forget the oring comes seperately on the S5 (89-92) stat.

Good Luck!

TehMonkay

iTrader: (-1)

My car had a stant in it when i bought it, only was in the car for 1 - 2 years and the car was running hot and when i took it out the rubber was already about to fall apart.

Piece of ****.

Put an mazda thermostat in and runs great now, only cost 20 - 25 dollars at the dealer anyways.

Evil Aviator

1. It's actually supposed to be fully open at 95C (203F).
2. Aftermarket thermostats are usually rated at the temperature that they begin to open, which in the case of the FC is 177-182F, which is only 1 degree difference from the Haynes manual. Most "180deg" thermostats are fully open at 200F.

For some reason, only the Mazda brand thermostat works properly. Replace your aftermarket thermostat with the Mazda brand (jiggle pin facing up) and then you can troubleshoot any problems that still exist.