Ka Kui

iTrader: (36)

Hi everyone, I drives a 1993 FD, and when i am driving normally with low rpm, speed around 70km/h, etc, after maybe 15 mins of driving, the coolant metre or the H - L metre in the dash boad wil rasie a little bit. Normal cars the metre will point between H and L. (Right in the middle or something) But for my FD, it will raise a little bit. (Let's say pointing half way betwen H and L is a 50%, my metre will be reaching around 55 - 58% off that metre on my dash board.)

My FD is a pure stock car, only have a Racing Beat muffler, that's it. Mechanically stock. I tend to sit inside my car and wait the car cool down for 3-4 mins prior shuting it down. However, after I shut it off, i am hearing some boiling water noice after i shut it down for a couple of minutes as well. Can anyone tell me what's wrong with my FD? My FD was leaking coolant before, and recently, I have changed a new Coolant Resovair from Mazda Dealer. I check my Radiator coolant level, they are fine. Any clue of what's wrong? Stock FD cooling system ain't enough for it? Please help me out, thx!!!!

Tom93R1

iTrader: (2)

The FD water gauge is notorious for being a useless POS. About all its good for is an indicator that you have reached a safe temperature to boost, and an indicator that you have already overheated. The gauge will get up to about half way then sit there until you are pretty much overheated, at this point it rockets up to the H.

If you want your gauge to be useful, search the 3rd gen section for the temp gauge linearization mod. Otherwise you should get a water temp gauge or a powerFC with commander to monitor water temp.

Ka Kui

iTrader: (36)

So by that means, my car is overheating? Any indication of which part is not working? Water tank? I have just installed a new thomostat recently as well, by the Mazda Dealer.

Mahjik

iTrader: (1)

Until you get some way to get exact temperature readings, no one really knows for sure if your car is overheating or not. Just buy an aftermarket temperature gauge, something like this:

http://www.rx7store.net/product_p/autometer%20wt.htm

When you see what your temps are, then someone can provide some useful information.

Twinnos

i got an aftermarket gauge and helps a whoooooooooooole lot and i filled it with only coolant from Peak 50/50.

Ka Kui

iTrader: (36)

Thx, then maybe i should get an aftermarket water gauge. But i still wonder, the stock gauge on the dash board isn't showing the right temp? Pointing half way is normal, right? Those aftermarket gauges have precise measurement eh?

Mahjik

iTrader: (1)

The stock gauge is basically a range. The middle of the gauge is for temps around 180-240F. It doesn't really move too much from the middle until you are approaching 240F. So you don't really have a good idea on what the real temp of the car is... The stock gauge is not linear.

Ka Kui

iTrader: (36)

If the middle of the gauge is around 180 - 240F. So what is the overheating temp? More than 240F? When I turn off my car, i can still hear some boiling water sound (After I shut my car down completely). Since I hear there are boiling water sound coming from the engine bay area, so i pop into my car and turn the ignition to the 1st stage, to let the fan turn on for 3 mins or more, then I shut down the car again.

Ka Kui

iTrader: (36)

Hi everyone, I had brought my FD to Mazda Dealer recently again, and they changed 2 switches for me, one is the Water tank fan switch, and secondly, is the water pump temp sensor switch. They said after they installed these parts, the car is back to normal temperature.
HOWEVER, today i drive to work, and back home at night, the engine bay area still hot. How long does it take the car/engine to cool down completely? I back home around 7:00pm today, and after dinner, i went out to check my car at 9:00, the hood still hot, so i open up my hood and the engine bay area still hot. This is not normal, right? My car is overheating, right? 2 hours normally should cool down completely, right? I am going to bring my car back to Mazda Dealer again, and see what they have to say...... Please reply for help, thx.........

Specter328

iTrader: (2)

My car takes quite a while to cool off from maybe 90c or around 194f. I'll check the exact temps tomorrow if you'd like.

Custard

i have similar problems with my FD... bubbling water after a highway cruise..PFC indicates around 105 degrees C and i have seen 114 degrees C on it after a short stint at high boost...

Can anyone offer advice on what normal operating temps are??

Greg

Ka Kui

iTrader: (36)

Yea, please help!!!

ericgrau

iTrader: (1)

Probably 80C to 95C. Any auto parts store will tell you what temp your thermostat is. But anything above 100C is getting bad. 115C or 240F sounds like it is already boiling or about to boil.

Overheating and knocking are the enemies of the rotary. 1 strong overheat or 1 strong knock can blow the engine. I hear FD's are unreliable partly b/c they have a poor cooling system and b/c they are tuned just barely well enough to avoid knocking. Basic cooling system upgrades are the temp gauge and radiator. Cooling system maintenance is also important. The engine should be retuned after any power upgrades to make sure it never knocks. i.e., With a good margin of safety so it never happens in the future, not just during the tuning session and not just "it's not knocking (for now), I'm not gonna tune". Turbo system maintenace is important to prevent over-boost (and the immediate knocking that results). Don't gamble your engine, read up and prevent the problems.

hhn2002

usually when coolant leaks, as a quick fix people will just fill it up with water. and when they keep doing that eventually there will be too much water and not enough coolant.
check that your coolant isnt just mostly water. a 50/50 mix of water and coolant should still yield a very radiant translucent green. try a coolant system flush and refill. it shouldnt boil while just cruising unless theres not enough antifreeze/coolant mixed in. make sure you know the difference between the already premixed 50/50 water:coolant and the 100 coolant. if you get the premix just pour it straight in. if not mix equal quantities. that should fix ur prob.ohh and make sure ur system is completely bleed= no air bubbles.

hhn2002

the car mechanics recommend you wait at least 4 hours b4 its safe to work on any hot parts of the car. so i'd say 2hours is definitely not enough. most engines are still hot after 2hrs.

Custard

thanks for the updates guys. i think the concentration of the coolant in the car is low and needs to be changed out..im quite sure its not distilled water either. previous owner installed a Greddy FMIC and this is probably robbing the rad of much needed air too. it also has a stock rad, which is not contributing as efficiently as a fluidine or koyo that seem to be the best upgrades.

is there any reason why the koyo's and fluidines are so highly recommended. here in South Africa importing parts from abroad can be a time consuming process. there are custom rad builders here..would it be waste of time to have one built..what are the key elements for a good upgrade..a thicker core, ablity for the water to have multiple passes before exiting the rad etc.etc.

its also pretyy hot here ..summer temps about 30-35 degrees C

some advice please before itake a decision.

Mahjik

iTrader: (1)

There are many aspects to cooling. For normal street driving, the main thing you care about is air routing/ducting. i.e. the more air you are able to force through the radiator, the more effective your cooling system will be. Increasing the thickness of the core without increasing the airflow isn't necessarily a good thing. If you don't have enough airflow, a larger core can have an adverse effect on your cooling system (i.e. you run hotter).

Koyo and Fluidyne are popular as those are two brands which are easily obtainable in the USA. Honestly, those are not the only two companies on the planet who know how to weld up a radiator. The main issue is finding a company who can produce a radiator which is specifically made for the car. Here's a post showing a radiator advertised for the RX7, yet doesn't have the things needed to be a direct replacement:

https://www.rx7club.com/showpost.php...66&postcount=9

With brands like Fluidyne and Koyo, you know you won't run into problems like the post above.

Ka Kui

iTrader: (36)

I still hear some water boiling sound after I turn off my car for 10 mins or so.... Is that bad? How bad is it? I have replaced a new thomostat. Will changing those Samco cooling pipes for radiator and turbo pipes helps?

Custard

Since i have a FMIC and it totally occupies the centre air dam of the front bumper, its almost impossible to try to route/duct some air flow to the rad without some fancy mods, how helpful will it be to change the fan temps to come on at 5 to 7 degress cooler:
Fan 1 A/C at 90C
Fan 1 no A/C at 95C
Fan 2 at 100C

Greg

Mahjik

iTrader: (1)

IMO, that's a little excessive. I would have both fans on high at 110 C, then go down by 5 for each of your others. I would still look to try to create some ducting for your radiator. You can duct air under the FMIC and then to the radiator:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/my-radiator-fmic-ducting-mini-project-651168/

streetpower

it is difficult to bleed the cooling system in an FD. the bubbling noise is air bubbles runing through the system.
you need to make sure ther is no leaks...pressure test the system
once there is no leaks you then need to fill the system completely.
go to princess auto they have a huge yellow funnel with adapters to secure it to your watrepump housing and athach it to the housing fill the system up with 50/50 premix and let the car vehicle idle for a good 15-20 mins do not let the funnel run out of coolant add as needed.
when all is said and done the next day before start up pull the waterpump housing cap off and check your level if it is low top it off and you should be fine.
pm..... me for more details
sean

ScrappyDoo

iTrader: (7)

Do yourself a favour and take your car to jim kutschke, a member of this forum, a rotary shop owner and generally great guy. He is in the Toronto area and the person I rely on for issues with my FD. His name on the forum is his name, "jim kutschke". There is nobody else in the GTA with the exception of Canjam Motorsports and Mazdees that I would trust with my car.

There are very few Mazda dealers in the GTA that have good techs to handle maintaining FDs. If you want to know my personal experience with some of the smaller rotary shops in the area feel free to contact me. My early mistakes may save you alot money. I will drop you a pm as well. Good luck getting your car sorted and whatever you do get your temperature problem diagnosed before you do some irreversible damage. (assuming you actually have a temperature problem)

streetpower

Lawyers spirit his question was not who should he take his car too and this is not the LOUNGE this is ROTARY TECH SUPPORT where forum members have technical questions and need answers seeing they are trying to learn and repair something on there OWN while communicating with other forum members.
i am sure if Jim @ Rotary Dynamics or Stewart @ Canjam or Dave @ mazdees was interested and willing to help this forum member they will be offering him solutions to his issue personally and i am sure the forum member knows about local shops.
Sean

QUOTE=Lawyer's Spirit;7395842]Do yourself a favour and take your car to jim kutschke, a member of this forum, a rotary shop owner and generally great guy. He is in the Toronto area and the person I rely on for issues with my FD. His name on the forum is his name, "jim kutschke". There is nobody else in the GTA with the exception of Canjam Motorsports and Mazdees that I would trust with my car.

There are very few Mazda dealers in the GTA that have good techs to handle maintaining FDs. If you want to know my personal experience with some of the smaller rotary shops in the area feel free to contact me. My early mistakes may save you alot money. I will drop you a pm as well. Good luck getting your car sorted and whatever you do get your temperature problem diagnosed before you do some irreversible damage. (assuming you actually have a temperature problem)[/QUOTE]

ScrappyDoo

iTrader: (7)

^^^^My post wasn't directed at you. It was giving the thread starter options to the dealership that he was currently using. If my post helps him avoid taking his car to an a-hole like yourself that is an added bonus. It sounds to me like you are upset that I wouldn't add you to my personal referral list. You and I both know the reason for that but if you've forgotten I would be happy to debate your skills and customer service in an appropriate thread elsewhere on the forum. That is if you have the ***** to try me, which I highly doubt.


Ka kui, drop me a line and I can have someone look at your car at no charge.

streetpower

typical lawyers or shall i say liar....i directed my repost to you and i am not offended nor intimidated by you if you understand what i said maybe you should reconsider you obscene and unproffesional reply. the forum member is trying to learn and figure out his issue with help from forum members. if he was looking for a shop he would of ask for recommendations which he didn't.....
as far as being on your referral list as i told you before i have been in this game long before you and my quality of work speaks for itself so you refferal list means **** as far as i am concerned or for anybody else for that matter...
because i banned you from my shop you are pissed off at me but you know what i do not care because rotaried are my life "streetpower cars are well represented" you could bad mouth me as much as you want but my quality work speaks for itself streetpower cars run the fastest in the quarter and streetpower tuned cars makes the most horsepower.
i personally know the other shops you talked about and you know what they are good shops but i hear and see horror stories from them as well and those about there engines and work ect so what i don't care because at the end of the day streetpower cars are at the track representing the rotary lifestyle and spanking on the pistons.
yes i am expensive but you got to pay to play......
yes i pick and choose the cars i work on because as i learned from my experience is people do not appreciate a mans labor and will not compensate for quality workmanship.
yes my shop in the past was run part time....but wait to see what streetpower is coming out with for next season......
and by the way Jim from Rotary dynamics and i are personal friends and i do not get my business involved with his... friend are friends business is business.
so you don't get all offened by me posting to you directly or name calling you lawayer liar.....
sean