ejmack1

Would this help in cooling? I have a Koyo radiator and am seeing temps climb right above 100C. Both fans kick on at ~85C, but I am still seeing temps rise up to as much as 105C.

Would I be able to completely remove the thermostat without causing negative problems? Its a new Reman so the thermo should be good.

spurvo

Hiya! Removing T-stat not a good idea USUALLY, in that the engine runs too cold and the ECU tends to run the engine rich to heat it up, and it runs like crap during that period.

BUT, you are having the worst cooling problems I can think of!!! Seriously, new rad, new engine, fans coming on at 85C, but still seeing temps over 100C, your car is posessed!!! Try pulling the T-stat as a temporary solution. If the temps go down, get yet another T-stat. If they stay high, keep looking.

Your car really is Satan.

DamonB

Not unless the thermostat is already bad.

Removing it completely is not recommended because with the restriction gone the coolant will in fact flow to quickly to spend enough time in the radiator to lower its temp. Many racing vehicles that do not use thermostats still install a "washer" to act as a restriction. Basically the same thing as putting them in the exhaust to prevent boost creep.

ejmack1

So if i "hollow" out the thermo would that work? Im at about a 50/50 mix right now, but i have never had a mixture of water and antifreeze cause high temps.... any other suggestions?

rynberg

1) Verify that both fans are actually coming on.

2) Replace the thermostat.

3) Fab up some shielding for the sides of the radiator to force air through the radiator. When you go with an aftermarket radiator, you lose the foam blocking on either side of the radiator.

DamonB

Removing the thermostat is never a fix. If the thermostat is bad (slight chance) you replace it. If it isn't the thermostat you fix what is wrong, not try to band-aid it. If you are sure the rest of the cooling system is working I would replace the thermostat even though it's new so that you can rule it out as a problem.

Did you have cooling problems before the reman? Things I would check-

Is the coolant FULL with no air?
Are both fans operating?
Are both fans running at the correct speeds according to temp?
Any hoses kinked?

Are you positive that the water temp sensor is good? Maybe the coolant isn't actually hot. Any overheat symptoms?

adam c

iTrader: (2)

Replace the thermostat with a Mazda factory unit. Don't buy an aftermarket one. Although this won't correct your overheating "problem", I recommend using about 1/3 coolant and 2/3 water, especially during the hotter months.

rx7racer11

your water pump could be on its last leg.. and its not performing its full duty

ejmack1

New Water Pump with new Reman... I could try to lessen the coolant and increase the water amount. There are no kinks in the system, I DO KNOW that my heater core in plugged, which I will be pulling the dash for next week to fix, but that never caused a problem before with my car runnin normally...

ArcWelder

Removing the thermostat is not the way to go. Like DamonB says, the system requires some restriction to allow the water to remain in the rad long enough to cool. I have drilled 3 holes in my thermostat, each about 1/4 inch to allow more coolant flow for the track. This was for summer use only. In the fall, temps were actually running too low(on the street).

If you have overheating problems, I'd look somewhere else.

I can add one more place to look:

Is the undertray installed and well sealed?

Mark

7racer

ejmack,

what kind of temps where you running before the reman?

ejmack1

honestly not sure... i didn't have a PFC or water temp gauge....

ejmack1

guys this is at a stand still, I haven't actually moved the car a long distance... just up and down the block.... i leave it sit and the temperaturs go above 100C

adam c

iTrader: (2)

With no fans, the car will get really hot if it isn't moving. At idle, the fans should keep it under 200 on even the hottest day

Trexthe3rd

Drain your coolant, flush the entire system with high pressure water. You have pluggage somewhere.
If there is nothing blocking the airflow to the radiator then you are definitely running too hot.

ejmack1

its a reman though

spurvo

So lets be a bit more specific. You are seeing temps climb to 105C, but you are only tooling the car around, not driving above 35 mph (which is roughly the minimum speed to get decent airflow over the radiator to get it to cool down through air flow means alone). Your fans are coming on, and the temp is going back down, but then comes back up once the fans go off.

Your car is behaving EXACTLY as it should. In a stock system, the fans are programmed to come on at 105C (221F) to cool the engine off. They shut off at 195F (roughly 90C) or so. If you turn on your parking lights, the fans should come on around 100C or so.

Or you can do the fan mod and keep the engine below 190F all the time!

Fan Mod for president!

7racer

I agree with spurvo. The only other thing is what happened with Zerobanger where he was overheating and found that one of his fans was burned out and not coming on. It took him awhile to figure out.

I have the pettit thermostat which opens at a LOW 76 degree C and a Koyo. Driving on the highway I get the car to 82....even in the warming Texas heat...but get me in stop and go traffic...ITS OVER...I creep to high 90's low 100's easily. I need to get my friend with the datalogit to turn my fans on lower.

The other thing that seems to help is to take your thermostat out and do that mod by removing that little dongle/toggle thing.....that seems to help

rynberg

Spurvo, he said his fans are coming on at 85C and he is creeping up to 105C with the fans on.. This should not happen at any reasonable ambient temp.

suprfast

ALL CAPS SO ITS READ... ITS THE SIDES OF YOUR RADIATOR. I HAVE THE SAME THING HAPPEN TO ME. I PLUGGED THE SIDES OF THE RADIATOR WITH PIPING INSULATION AT HOME DEPOT. I JUST JAMMED IT IN THERE TIGHT SO IT WOULD NOT BUDGE. COVER ANY OPENING THAT WOULD DIRECT AIR AWAY FROM YOUR RADIATOR. with that being said my temps never see above 95 when driving the **** out of it on autoX courses and fans on.
kris

spurvo

Rynberg, you be correct. I didn't read it right. This is too wierd for me...

ejmack1

I dont think plugging the radiator sides will help when at a stand still....

ejmack1

Ok let me ask this question... there is a coolant temp at the rear drivers side of the engine correct? and at the thermostat. Which one shows the temp to the PFC? and which one controls fans? Am i correct that there are two coolant sensors or did I read that wrong somewhere?

neevosh

here's some useful info. http://www.mazdamotorsports.com/weba...ubject=cooling