Bearzah

iTrader: (6)

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Ok... Aftermarket (brand Equis... Knechts) mechanical temp gauge mounted under thermostat (where oem temp switch was). Normally runs 190* with oem gauge around 1/3rd... Just to left of temperature symbol. When at highway speeds (65mph 3200 rpm) it rises to 195* and up to 200* when accelerating under boost or up a long hill... This whole time the oem gauge doesn't move. New water pump, fresh cooling system flush, about 50% antifreeze, water wetter and and newer 180* Mazdatrix thermostat (ran same temp with old thermostat). Its running 2 x 10" 1200cfm electric fans on 180* switch. Ambient temp 85-95*
Am i running to hot?
What's to hot?
Would a lower temp thermostat be a good idea?

Thanks guys, your always a huge help.

Jeezus

iTrader: (4)

You are running fine for a turbo'd car.

Do not rely much on the stock gauges.

Too hot IMO is 220, but different strokes for different folks. Are your fan's on when you are on the highway? Turn them off, they are hindering air flow at that speed. Also check to see if you have all the radiator panels in place; both sides, top, and bottom.

Bearzah

iTrader: (6)

Both fans are puller fans mounted on engine side of radiator. All shrouding in place except for plastic one sense not using clutch fan. Not really sure how to disengauge fan at highway speeds WITHOUT using manual switch... I'll end up forgetting to turn it back on... Which would be bad.

bad 83

iTrader: (3)

It would probably be a good idea to drop in a 160* thermostat. I run one in my TII FB with a Taurus e-fan. Normal driving on the highway my temp stays about 175* to 180*. I would set the fan controller to kick the fans on at 170*. If your running a drawthrough like the one in your avatar, I don't think you will ever get the engine temps down without any intercooling.

Bearzah

iTrader: (6)

Yup.. Running what's in my signature.
Maybe i'll look into a 160* thermostat... I'll wait a bit longer to see if i get more replies.

Attila the Fun

iTrader: (1)

Not too hot, yet.

"Too hot" is 230 degree or more. At that level, you're skating on thin ice. The seals might take it; they might not.

The lower thermostat might be OK, but there will be other issues from running too cool. A stock Mazda 180-degree thermostat is really the best.

Jeezus' advice was good, especially that about making sure your airflow through the radiator is at it's best.

82transam

iTrader: (18)

It's funny, I was going to post a thread like this one today since its been in the mid 90's the last few days, guess I don't have to now
On my 12a fb the water temp will get up to 210 with the a/c on pulling up a hill or something on the highway, to me this seemed too high, but if what you guys are saying is correct I shouldn't have to worry then...
My TII FB has a huge aftermarket radiator in it (and no a/c) and rarely gets even close to 200, even under boost etc

j9fd3s

iTrader: (3)

yep, anything over 230F/110C and you're on your own.

just cruising around 200-210 is perfectly fine

82transam

iTrader: (18)

Good to know, thanks.

Bearzah

iTrader: (6)

I installed a 170* thermostat (Napa #3) yesterday and things are looking good!
I haven't seen over 180*
I plan on taking it up Mary's Peak, we'll see how she does :-p

jinxed4dub

iTrader: (7)

are you going to the rotards meet Saturday? If so I want to see how you have that temp gauge wired up, I've never installed aftermarket gauges, and seeing it first hand would solve any question I had. I want more precise temp readings. not to mention aftermarket gauges are worth like a bazillion HP

titorx7

hey guys i also have same issues, i have an 83' rx7 with an SE 13b with an 12A intake plate to make a 4 port 13b, the engines has an aggressive street porting, also, one 14" e*fan that is always on but control by swith i build, holley 600 4br, RB heater, no cats, no oxygine pump, if i'm driving crusing or hard on the highway or neighthood street the temp stays around 190* -200* but once i stop at a red light and idle for a little the temp tents to raise up to 210*-215* it never gets to 230* but have has gone up to 220* before, i also have a aftermarket temp gauge coming from right below the thermalstat, cuz i don't trust the sensor that come from the bottom left of the radiator, my question is that is causing the temp to raise when idle, at one point i was thinking of buying a dual 10" fan and build around a metal sheet that would cover the whole radiator to see it would a make complete radiator suction when the 2 e* fan are on, what do ya think i should do,. pls help.

Bearzah

iTrader: (6)

I see you have A/C.... is it running when your temp gets out of control?

I suspect your water pump. A replacement is cheap (under $40).
http://www.napaonline.com/MasterPage...r+Pump+-+Remfd

While you have your cooling system drained go ahead and cover all your bases.

Get a new thermostat ($5) --> 170* works great - which is at Napa Auto Parts Part #3

run a cooling system cleaner through = ($3)
http://www.napaonline.com/MasterPage...ditive+-+Flush

flush the system ($7)
http://www.buyhardwaresupplies.com/?...emNumber=85973

and throw some Water Wetter ($7) and Antifreeze ($10) in there
http://www.turnermotorsport.com/html...CT_ID=1-WW-12Z

The whole process won't take more than a short afternoon and yield a much more efficient cooling system.

Good luck

titorx7

yes i have ac , it works great too, it doesn't go scrazy , but currently i'm not user it till i fix this temp. problem, the engine only has 3,500 mile within 6 month of running, its a weekend car not a daily driver. , the motor has been running great, i can not be any happier on the way it is performing, yeah i guess i can start by changing the thermalstat. what about if i'm running a little too rich on the carb. can that cause to heat up too, i know for sure if the car engine runs lean it does heats up , but not sure if is very rich.

Bearzah

iTrader: (6)

generally LEAN = HOT... not rich

j9fd3s

iTrader: (3)

if you're overheating when its stopped it probably needs more fan. when you're stopped there is no air flow, so the fan must provide it.

arghx

iTrader: (3)

Just about every Mazda rotary since 1970 (12A, 13B, 13B Renesis) has had a thermostat that cracks open at 82C (180 F) and opens fully at 95 C (203 F). One interesting thing to note is that Mazda has consistently kicked the electric fans on to full speed at 108 C (226) on both the FD and the Renesis.

The Renesis turns the fans on at low speed when temps reach 98 C (about 208 F). Most other modern cars I've seen (turbo Subarus for example) switch their electric fans on at 95 pr 98 C. I think it's fair to say then that the engine can run for sustained periods up to 210 degrees F, because so many cars have been doing that from the factory and continue to last.

bad 83

iTrader: (3)

This is true, but the rotary engine can be damaged alot easier from overheating. I would just like to keep the engines temp in a more tolarable level than putting it on the edge of overheating. The reason the car manufactures want them to run that hot is promote better fuel mileage. That's it.

trochoid

iTrader: (6)

Is the 1200 cfm for each fan or total cfm? If it's 1200 total, the fans aren't pulling enough air. You should double it, particularly with the turbo.

I see 2 problems just from the pic. You need a full sized shroud to cover the radiator and you're missing the windage tray underneath. Also, what's the cfm rating for that fan?

And for both of you: If you're engines are overheating at stoplights, you're not pulling enough air, the radiators may clogged up, reducing efficiency and both probably should have upgraded radiators, particularly with a turbo. I would also add header/turbo wrap/blankets to reduce under hood temps. If the temps are raising during driving, then the fans are running and slowing down air flow. At highway speeds the fans should be off and free wheeling.

Not heeding my own advice, I'm running a 1200 cfm fan on the widebody with a 1/2 sp-1/2 bp 12A. I can get away with it because I more than doubled grill opening with the widebody kit, modded the windage tray and added an FMOC. This same fan caused my basically stock FC to overheat on 90* days in stop and go traffic. Had to go back to the oem clutch fan.

I have a thermo switch on the electric fan set to come on at 180*. Temp, read with an Autometer guage, rarely sees anything above 190*. I have seen near 200* in traffic on very hot days.

Bearzah

iTrader: (6)

1200cfm EACH on a temperature switch.
I appreciate the advise, but, as i already stated. It only warms up at highway speeds and actually runs cooler at idle or in traffic. I already installed the earlier 3 row radiator and fmoc. I suppose the fans might be inhimbering air flow at highway speeds, but, i can't think of a way to disable them AUTOMATICALLY (without a manual switch).
The 170* thermostat swap seems to have solved all my demons. I haven't seen more than 190* (or just under) sense than.

DivinDriver

iTrader: (15)

To add to Trochoid's great points; if your antifreeze mix is incorrect or old & contaminated, it can't transfer heat as effectively. It doesn't just change the freeze/boil point, it makes a big difference in heat transfer capability.

80's old school

iTrader: (7)

If you look at the wiring diagram for your car you will find that you have a switch on your transmission that "switches" when you are in Overdrive.....

Study the wiring diagram.....install a relay to this OD switch. Now when you are driving down the road and in top gear, fan off....no extra drag on alternator, no slowing down air flow through fan.....

See, now wasn't that easy!!!???

Bearzah

iTrader: (6)

Yup, that would work great IF i had a 84-85 transmission :-p

80's old school

iTrader: (7)

What tranny do you have??? Hell even the old 4 speed in my SA22 has the OD switch....