Overheating Issues
 

Hello, once again I am back with rotary problems.

The car itself is driven seldomly, and when it is driven it is sideways. I recently had to do a radiator flush, because a track did not allow coolant in the system.
I ran water, thought it was getting warm because of the water, reverted back to coolant.

Now when I drive around town, it gets up past 210, which makes me immediately slow down and pop the hood, trying to get it too cool off!!!!!
I have a serpentine belt system.. should I run a smaller water pump pulley to make the water flow faster???
I also have not checked too see if the Thermostat in the car is sticking.. I am gonna start there when I get home. Should I remove the thermostat because drift car? ORRRR
(as I believe) should I leave a stock thermostat in and run a smaller pulley?
Any advice would be awesome.

Without knowing what Series of car you have you are gonna get generic answers.
That is why there is a BIG thread up top to read before you post.
State your car and mods please.

Water should run as cool or cooler than antifreeze. You have other issues. Do you have stock fan and shroud?

Sorry m8,

I have a S4 13bt 3mm apex seals, ported, black magic fan (electric, I have it turn on at 170* so its on all the time) Serpentine belt kit, aluminum radiator, intercooler,
no heater(i didnt remove it, it was gone when I got the shell)
I also premix with idemitsu rotary premix, and run AT LEAST supreme from chevron, or ethanol free prem.

You should look at the ducting and particularly if you have the Plastic belly tray on the car as it really DOES help the air stay where it is needed to go..Rather than suck it out once the car is up to speed.
Also if you have a Black Magic fan,do you have a Shroud around it?..not just the shroud that the fan is built into.
Encasing the rad and fan together will allow the fan to suck air through the fins in order to cool,.
If the Fan is just sitting there then it is not half as effective as what you think it is,as the rest of the rad is not being used,and no air is even getting to those areas to cool off.

lets see a pic of your fan setup

It is just the fan mounted to the Rad... There isnt a Shroud on it.
Do you guys know where I can get one ? or am I gonna be cutting a stock one up?

and as far as the ducting on the bottom goes I will look in junkyards etc for some, but I see the logic of the wind through the fins in the rad keeping it much cooler, so my #1 priority is that

If you can,that would be great..

that way you can get more "critique" and suggestions as to where you can go with the solution.
Right now,it's like working blind..lol..

Like,I can suggest a couple CAR fans that would do just as well or Better than that Black Magic you have...BUT if your setup is already "half way there" no sense in tearing apart something that can be saved,but just modified.

Agree water is much more effective at cooling than the coolant. However you should run some coolant for water pump lubrication. If you're in doubt change the thermostat, they're not that expensive. That fan setup is probably less than ideal without a shroud. It is likely at least half of your issue. At speed it may even be counterproductive. Anything that will increase high pressure in front of your radiator will help, that includes a belly pan. Upholstery foam is also effective at plugging any gaps around your radiator to force mores air through it.

I will go home and take pictures of my current set up. I have a front mount intercooler as well.

I will be getting a fan shroud, either made or buying one, does anyone have ideas where to go for good quality stuff?

As far as the belly pans, can I rip one off of a stock rx7 and use it, or are there aftermarket options?

This will be some of the problem as well.

No one has really answered my fan shroud question.. where would be the best place to acquire one??
also, are there any aftermarket water pumps that do better than the stock ones??


Ideas on pulling thermosat vs putting one back in at the 190 stock temp?

Try a little patience in this section please as it is basically ALL Series of cars in one section and Guys usually frequent the main sections.If you accumulate posts then you can go to your specific section where more answers can be given by more members.This section is sort of off the beaten path,so less frequented by members and may take a bit to get answers.
We try to give them If we can,but sometimes can't accommodate!..

Look up Merc Villager E fan.They have a Built in shroud that will encase the whole rad,and it is like 5 minutes of trimming some plastic and making a few bent brackets and Presto!..Perfect E fan and shroud.
I am suggesting this,as it would take you more time( In my opinion) to make a shroud around the Black magic fan...and honestly the Villager fan ( Or a FIERO V6 Fan) will fit without having to construct anything at all.it is also Just as OR more efficient than the Black magic fan is.
The belly tray?..stock plastic belly tray.
Thermostat?.STOCK OEM Mazda thermostat.( NO STANT crap!)
Water pump?no aftermarket Upgrade available as far as I know of,BUT you can go with a KOYO N-FLOW radiator and that would help the Cooling.(the Villager fan fits that too.)Griffin makes a Super-duper rad too.Need to make that one fit though.

Sec Gen parts is a good place to find stuff on forum here.

The Black Magic fan is supposed to come with a shroud. I don't understand how it could be mounted to the radiator without one. Anyway, you could maybe contact Flex-a-Lite to see if they will sell you a shroud. Otherwise, you could make one out of aluminum or fiberglass.

Mazdaspeed Motorsports Development sells the 20B water pump as a competition pump for 13B engines. However, I don't think that it will help your situation.

If you do pull the thermostat, then you need to tap and plug the hole below the thermostat. It is usually a very bad idea for a street car to run with no thermostat. The thermostat should open around 180F, not 190F.

Thanks for your info m8, much appreciated. And the black magic fan did come with a shroud, https://www.rx7club.com/members/13bt...rs-side-54295/

But as you can see it doesn cover my "Koyo Radiator" fully, as was the expressed opinion above.

I Hardly ever street this car, generally only when I need to do some work, at a shop down the road, or if I just feel like hooning it up a little bit.. Its not my daily driver, nor will it be. So should I pull the thermostat? I have heard multiple different things on this subject.

on the "Buying a different fan" route, I have seen multiple builds with this fan, and they run cool, I want to get my set up so that it does the same. I do not think the fan is part of the problem, only that it doesnt have a correct shroud...

also, added an album to my profile with more pictures!

IIRC, the FC is similar to the FD in that there is a port to allow coolant to by-pass the radiator and go directly back into the engine to aid warm-up time. Normally it's only open with the t-stat is closed. If you remove the t-stat, it'll be open all the time.
In my experience, the engine ultimately doesn't run any cooler, it just takes longer to warm up.

^ This.

The primary purpose of removing the thermostat is to eliminate a point of failure. The engine will not run any cooler, it will take longer to warm up, and it will run like crap if the car is driven at varying speeds for more than a few minutes.

The FC has a bypass type thermostat like the FD, so the bypass hole MUST be plugged if the thermostat is removed, otherwise the engine will cool WORSE than it would with the thermostat installed. See this link to learn more about bypass thermostats:
ARE Cooling

Well I highly doubt the thermostat is failing, I drove the car to work today (I have a date tonight, sue me) and it stayed at 180* the whole time, no issues. It was a lot cooler today than other days though. My fan didnt even kick on, I dont know what to do... Its really only when I drift, (staying up high in the rpms) or its really hot outside that I even have an issue.
which Is why a fan shroud would help alot. Should I go to a local fiberglass/aluminum guy and give him a rough Idea of what I want?/hope for the best????

You have forced induction. Consider an inexpensive boost activated water injection system. Water has a high 'specific heat'. Injecting a little into the intake will carry alot of heat away from the combustion chamber when it changes phase from liquid to vapor. That should help the temp spiking your seeing at prolong periods of boost. As a side benefit, it tends to lower knock values and controls carbon. And with a properly sized nozzle you won't need to change anything on the ignition or feel any change in power. Go to the Auxillary Injection Section and study up on the stickys from HC. Such a system is simple, reliable and not that expensive. My .02

Injecting water into my motor???

id rather set up my windshield wipers too my rad, and pull the handle back and cool it off that way... I never let it get above 200* as is so that would work.

I want to not let it get up that high, and injecting water is something I have never heard mate, I appreciate it though.

I've been stressing that you need to cover more of your rad to get better cooling efficiency.
That alone is your Problem.Your Efan just isn't taking the heat out of the system.
This link shows a different rad and fan setup,but notice that the fan covers more of the rad than yours does.
LINK:How To Properly Install An Electric Fan

the pic here is my car with the Merc Villager Efan setup on a Koyo Nflow.
Notice that the whole rad is covered.

Water injection is not a bad thing. you need to do a bit of research . :icon_tup:

You probably dont have any cooling issues do you??

I Understand that I need a bigger shroud, I am just looking at viable options for making my own? as I dont want to just piss away the fan that I bought because the shroud doesnt fit over the whole rad, I will just make one.

Flat aluminum or fiberglass??

From the little I did, I would have too say im interested.

But if my set up isnt working correctly, I dont want too add more things that can go wrong, it is very very cool too see so many water injection applications, I literally had never heard of it before.

I will work on that stuff after I get my fan shround on ;)

Yes, the technical term is called "Anti-Detonant Injection" (ADI), and it has been used in high-performance aircraft for nearly 100 years now. Professional-level ADI is typically a mix of demineralized water, methanol, and water-soluble oil. The mix depends on the application, but typical ratios are 60/39/1, 49.5/49.5/1, or 99/0/1. It is a legitimate method for reducing detonation, and it cools and cleans the engine. However, you are correct, it adds another point of failure, as well weight, and it is another fluid to service on a regular basis. I agree that you should worry about the fan shroud first. You can consider the ADI system later, as it may be a good idea to have ADI operating during drifting events.

This will corrode the radiator.

As much as I like the other articles on Aaron's website, I don't really agree with about half of his e-fan write-up. The shroud should really cover the entire radiator core, two fans would be a better choice than one in an application with a short stand-off, and I don't like his method of controlling the fan.

It's your choice. Below is a link to a high-quality radiator with an aluminum fan shroud. It is not for an RX-7, but you can get the main idea. The stand-off distance between the radiator core and the fan should be about 1" minimum. Optimally, the distance between the radiator and exit hole would be at least the distance of the height of the radiator core, but this is not usually practical on a street car.
Radiator And Fan Assembly - Mazda3 2004-2008 - Competition - AWR Racing Store