Steve Dallas

I have the Koyo S2 radiator, which is higher volume than OEM. I put 2 gallons of Mazda FL-22 and 1 gallon of distilled water in it, which calculates out to 37% coolant.

j9fd3s

its been my experience that the water seals loose their resilience to overheating as they get older.

i've run the older engines up to 110C/235F with no issue, but at this point an un rebuilt one is 25 years old, and at that age 110C is probably not a good idea...

drebbrnator

If you checked this after the track, these could be clean even if your seals have a small leak. Once your car is up to temp for a reasonable time, the water will cook out of your oil.

The best time to check would be after several short trips, when your engine doesn't have time to completely warm up. Also, rather than check your dipstick / cap, take the plug out of your oil pan, and just get 8oz or so out, and tighten the screw back up.

The dipstick and cap are known to get sludgy under normal operations, but if you have any water in your oil, it will settle in the bottom of your pan, and get drained out before anything else. So if you pull out 8oz of water; you've got problems, otherwise, you're fine.

Jesus Martinez

I have that oil analysis test kit. That would probably be the most accurate way to gauge. Cause lately it hasn't had that sweet coolant smell anymore, and the reserve bottle doesn't seem low, but if it is small amounts, I won't notice till its low.

My car is a 2007.
I have the Torque app, that is what I was using to read the temps. I just wasn't sure if they were accurate since my ODB scanner is those $15 ebay ones.

I have been told by instructors that I am over driving the car. I get understeer and I always over drive to "compensate" even though it does the opposite of what I want to accomplist. I am working on that. Considering that day I went 3.5 seconds faster than other times, I am unsure if it was me just going faster, or technique in those corners.


Also, I want to go at the end of this month back to the track, I haven't upgraded any of the coolant components, I check the coolant level, the foam is still in place around the radiator, last time I did 120mph (stupid and risky I know ) I got flashing CEL which means I have a misfire (again checked with the odb scanner and torque app).

I did the tune 15k miles ago, but I drive the car at the canyons, and have done maybe 4 track days on the car now. What do you guys think? It would be stupid to take it back out so soon without fixing stuff first right? My engine mileage is 80k so its "nearing the beginning of the end of its life span"

Steve Dallas

Do it. Blackstone can tell you exactly how much coolant you have in your oil.

I'm not sure what year the water pump was improved. You can search here for the answer. There is some disagreement about whether there was actually anything wrong with the design in the first place. The water pump is probably not the cause of your overheating problem, but could be a contributor.

Any OBDII scanner that transmits data is fine. They don't change the 1s and 0s that are streaming across. Torque is accurate as well and is a good app to use.

If you are experiencing understeer, you are too fast in the corners. The only way to solve it short of reconfiguring your suspension is to carry less speed into the corners and/or accelerate less out of the corners. Your lap times will actually fall when you drive more slowly and smoothly. Any time you are losing grip, you are also losing time. An obvious side benefit is your drivetrain gets a bit of a break in the process.

120mph on the track is fine. On the street, it is indeed stupid and risky.

You are playing with fire if you don't solve the cooling and other problems before taking it back to the track. Can you afford to push it off a cliff and walk away? If not, you need to get to the bottom of the cooling issues.

If I were you, and remember that I do not have your car in front of me to diagnose, I would upgrade the radiator (and probably hoses while you are in there), replace the coolant, replace the water pump, replace the thermostat, perform the fans on low mod, straighten oil cooler fins. A car that is tracked frequently has special cooling needs, and the S1 cooling system is inadequate to that task even when healthy IMHO.

Is your undertray intact? Do you have a cat? Is it healthy?

Tracking your car puts a lot of stress on the ignition among other parts. You can assume its lifespan is half what it would otherwise be. If you are seeing misfires, you need to get to the bottom of that too. Any other codes?

Other things you need to be doing are changing the oil after every track day, changing the transmission and differential oils at half the recommended intervals, premixing oil with your gas, staying on top of the brake pads and especially brake fluid.

Are you taking full advantage of any cool-down laps you are afforded? Can you drive the car off the track and onto the highway for a quick 5 mile round-trip drive to cool the drivetrain and brakes?

talonhart2

I live in the desert in socal where the ambient air has been about 115F the last week. My oil and coolant temps have been chilling at around 220-230F when I drive during the middle of the day (according to my prosport gauges). My factory gauges are in the usual spots. Do these numbers seem dangerous to you guys as well? Car seems to be running great but seems sluggish once the temp gets up that high. What do you guys think of this?

Steve Dallas

You will get all sorts of answers to that question. I don't think any of us have any hard data. I feel good about things maxing out at 220 under those conditions. I live in Texas, where we also see temps in that range in August. Realistically, there is only so much any cooling system can do in harsh conditions. I am fortunate enough to have another vehicle, so I just don't drive my 8 when it is that hot outside.

Getting sluggish in the heat is normal for 8s. Mine is at its fastest during the winter track season.

Jesus Martinez

I want to say yes, I do a proper cool down lap. It is maybe 4 miles from the track to the freeway, so usually I will go out and get gas around noon

Nisaja

Sorry for reviving a fairly old thread but, well, any updates? Is the car fine?

I'm doing a lot of research on overheating these days, and, just like the other member here who asked this (but never got an answer) I too would love to know if 230F is bad for our engines. A lot of people here seem to think that 220F is when you start to lose a coolant seal. Some say that when the temp needle moves, it's pretty much game over. It's even in the new and potential owners thread!

I have 2012 with 2500 miles, and when idling in 95F weather, my car hits 221F. I freak out, turn on the heater and watch it drop to 206. As soon as I turn the AC back on, there it goes back to 220F

Now I get how to fix an overheating issue. Better water pump, bigger radiator, faster fans etc etc. But what I don't get is why do I have to deal with this with a fairly new car! I can only think of two things.

1) The stock cooling system is inadequate
OR
2) This is how the car is supposed to be.

So which one is it? What is the REAL danger temp here?

It actually helps a lot. The heater core acts as a secondary radiator. I've done it when i'm stuck in traffic. My coolant drops from 220F to 206F in like 2 minutes with the heater on.

nycgps

iTrader: (1)

something wrong with ur car.

most likely ur fan motors having issues.

Nisaja

Yeah that's what I thought too, until I met about 15 other RX-8 owners in my area. ALL of them see similar coolant temps. My car doesn't jump to 220F in a minute. After about 30 mins stuck in traffic, it slowly creeps up to 220F. And how can the motors fail at such a low mileage?

Steve Dallas

I certainly do not see that drastic of a change when I turn my heater on. Maybe 2 degrees F.

I think we have been over this several times now. If you want to see your coolant temps drop drastically, do the fans on low mod. All it takes is a switch and several feet of wire. It will make your cooling system more effective from 0 to ~50mph. I did it and use it all the time. In fact, when I am starting my cool-down lap at the track, I reach down and flip the switch and watch my coolant temp drop from 210F to 180F in only 1.7 miles. I turn my fans on any time I am sitting in traffic or driving slowly in the summer. BTW, summer temps where I live sometimes exceed 110F.

Another thing you could do is install the Koyo S2 radiator. It is an all-aluminum design that has more cooling and coolant capacity over stock. I think mine was around $300 and took ~3 hours to install. It definitely helps with cooling, but the main reason I did it is for reliability. The plastic bits on the factory radiator will eventually fail and can cost an engine. Your car is new enough that you shouldn't have to worry about it for a while, however.

Here is a chart from the data log from one of my track sessions last month. Under unusual circumstances, I turned the fans on low 3 times. The first 2 were caution flags. The first caution was 1 lap, and the 2nd was about 1.5 laps. The 3rd was my usual cool-down lap. You can clearly see how effective the fans on low mod is.



.

Nisaja

Those are great temps Steve. I know that fans on low make a big difference. But when i'm hitting 220F, I'm always idling, and the fans are already on high speed. I know that a bigger radiator and faster fans will fix it.

However, that doesn't answer my original question. Is 220F really bad for our cars? Many say that you can lose a coolant seal at 220F. Many say you can definitely lose a coolant seal at 230F. And if so, why do all stock cars hit 220F in 95F humid weather when idling in traffic? Why did Mazda make a coolant gauge that moves after 230F?

Jastreb

iTrader: (1)

There's nothing magical about 220F. There's nothing magical about 230F either. Let's think about the ways coolant seals actually fail. I think there are 2 basic ways:

1. The rubber of the o-ring seals breaks down over time. The molecular structure is degraded due to heat and exposure to the reducing environment of the coolant. This is an aging phenomenon, where the rate of aging increases with temperature. It is helpful to think of an aging parameter that is proportional to the coolant temperature X duration of exposure to that temperature.

2. The geometry of the mating parts is deformed due to a temperature excursion (aka the housing are warped), and the o-rings are no longer compressed. I don't remember the temperature at which this may happen, but I believe it is above 240 F. This is more of a sudden failure that could occur if you ever exceed this temperature.

I don't know if you are aware, but the Series II actually have 3 fan speeds. The ECU doesn't set the highest speed until 226 F. What you actually hear when you are idling at 220F is the fans on medium speed. The ECU will also spin the fans on high as a fail-safe if your coolant temperature sensor fails. So even if you consider the high fan speed to be the ECU's emergency cooling mode, it still shows that there is nothing catastrophic about 220F. The stock idiot gauge moves at 230 because if you made it to that temperature there's a good chance you have a problem in the cooling system, or the driving conditions are unsustainable.

So to answer your question about 220F leading to engine failure. I guess this is how religious wars get started. A Reputable Engine Builder (praise be unto him) once said "The Renesis engines are failing because the coolant seals are only good to 220F". What he probably meant was that above 220F the coolant seals age faster, which eventually leads to pre-mature seal failure on cars that are above that temperature a lot. What many have interpreted that as (and I also thought that way once) is "Thou shalt not let thy coolant temperature reach 220F, for if you do, lightning from the heavens shall strike down upon thy engine."

So in your case, Nisaja, since you are in traffic a lot, and in a hot climate, upgrading the cooling system is a good idea if you are concerned about maximizing the life of your engine.

Steve Dallas

Any time you are idling or driving under ~55mph, you can turn your fans on to keep you from getting to 220F in the first place. You can almost use the tortoise / hare analogy here. Keep the fans running--even on low speed--to keep the temperature from rising too high. Slow and steady wins the race. If your coolant temps exceed the programmed threshold, the ECU will kick them up to medium anyway, which is sort of like having the tortoise transmogrify into the hare. Relying on short bursts of fans on medium when everything is already heat-soaked is not going to get it done for you. The hare always loses.

IIRC, I tested (and data logged) this approach for you last summer, when temps were near 100F here. I proved that driving my car at speeds of 0 to 55 with the fans on low all the time kept my coolant temperature significantly lower than driving the same route while relying on the ECU's control of the fans alone.

Try it. It's reversible and nearly free.

Nisaja

True. The S2 has 3 fan speeds. I assumed the medium fan speed is equal in speed to an S1's high fan speed. Weirdly, my car goes into that fail safe mode after extended periods of time stuck in traffic. After about an hour or so, the fans just stay on even while moving. It would stay on even after turning off the car and starting it back up. But if I leave it for 30 mins and start it, the fans work as normal. Maybe Mazda realized that running the fans all the time can help cooling? It only happens after about an hour of stuck in traffic, when the fans constantly cycle on and off.

Believe me man, I too was one of those guys. I'd never let it go over 220F. I freak when I see 215F. Hell I still do!

Why should I upgrade the cooling system in a fairly new car? This is my question. Why do these cars hit 220F when all the components are new? Didn't Mazda catch this when hot weather testing it? I'm sure they did. The only thing I can think of is, it's normal for the car.

The new and potential owners thread, and many other mementos on this forum, claim that 220F is bad. 230F means new engine. However, everyone now seems to say that 220F is not really harmful for our engines. I'm still afraid to let it get up to 220, because that thread has traumatized me lol. But you guys keep saying it's fine. I can't believe that all this started from one guy's "guess".

Anyways, if 220F is not harmless, and the temp needle moving at 230F is not "too late", then I propose to change the "new and potential owners" thread. It says that 220F is where you start to lose a coolant seal. If Mazda says the seals are good up to 240F, then it should not be there. It's seriously misleading people.

True. It works. I agree. But weirdly, my car does this after sitting in traffic for over an hour. And that's when I hit 220F. The fans stay on high (or medium since we have S2s) even when moving. They stay on even when the coolant temp drops to 186F.

So the problem here, really, is either the cooling system is not powerful enough to handle 98F weather, OR, that's just how the car is.

B-rahd

I just bought an rx-8, and for some reason when I drive in the highway for an hour or so, when I come to a stop my rpms drop under 1000 and most of the time my car dies. If it doesn't die, or if I start it back up, I have no power until I hit about 3000 rpms in 2nd gear. I'm very new to all this and I have no idea what's going on, I saw that it might be a fuel pump issue, but like I said, I have no idea. I need help.

Nisaja

You need to start your own thread man. This doesn't match the OP's question. If you don't start your own thread, you won't get a lot of replies.