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Hey all,

As the title says, my NA8T is running a bit hot at the moment. I just moved house (3 weeks ago) and I now live on a dirt road that is very very rough. As such I can only drive on it in first gear.
By the time I get home after driving nearly one kilometer up the dirt road in first gear, the car is over heating (can hear the water boiling).
The cooling system was flushed no more than 2-3 months ago.

I'm going to get a new radiator as the original, brown stained shitter is in there at the moment and being turbo it's putting out more heat the factory intended, but, has anyone or is there a way to have both fans running at the flick of a switch?
Surely an auto elect can wire something up like that, but is it worth it? Will a new radiator be enough?

try Redlines Water Wetter with distilled water as well. move the rego plate if it's in the way.

Also, if the new rad doesn't come with a higher pressure rated cap, then you can use a NB8 rad cap, or equivalent, which is rated at 1.1 kg/cm2, as opposed to the NA8 cap which is a rated at 0.9 kg/cm2.

I put a new 1.3 cap on yesterday, and I didn't overheat today, so it could be working (?). Just on that, how does the cap make that much difference?

SMK, my number plate is a sticker, but there's an intercooler in front of the radiator anyway.

radiator cap (which you already have) , new higher temp (or was it lower temp ... ) thermostat from trackdog racing, radiator cooling panel (which you already have), new radiator (cooling pro in my case) , redline water wetter , and distilled water. i was having overheating issues on the track and since doing all this the issues have been solved, so far, but i haven't had a really hot day at the track yet....

you really should get this 100% sorted before winton mate.

I'm trying to buy a radiator today, so should be sorted by Winton (fingers crossed).

Was going to start a new topic but this seems right up my alley


On our run tonight with the NSW'ers we were stuck behind a bus going up a long hill, my temp guage suddenly started to cliiiimb and went right to the end before I got to a spot where there was room to pull over. After lifting the bonnet it was dribbling coolant out the overflow on the expansion tank. We ended up running the fans for a while, topped the expansion tank up, and the temperature went down to about 1/3.

Ended up limping it to my friend's house with the aircon and heater both on, no more problems on the guage.


I have a cooling pro radiator waiting to go in, should I replace anything else while I'm at it?

It did start bubbling and dribbling again when I pulled up here, but hadnt gone up on the guage and i didnt smell any coolant while limping it here like I had when it boiled earlier

Adam_NAclubman wrote:I have a cooling pro radiator waiting to go in, should I replace anything else while I'm at it?

Fatty wrote:radiator cap (which you already have) , new higher temp (or was it lower temp ... ) thermostat from trackdog racing, radiator cooling panel (which you already have), new radiator (cooling pro in my case) , redline water wetter , and distilled water. i was having overheating issues on the track and since doing all this the issues have been solved, so far, but i haven't had a really hot day at the track yet.... .

further to what i said earlier, i since remembered that the cooling pro already comes with an uprated cap so need to buy another one. the water wetter may not really be necessary and thinking about it now i probably would skip that , run the car without it and then only add the water wetter if the overheating issue persists.

Is there anywhere I can get a thermostat from quicker than TrackDog? I think I'd like to change that before the radiator, I have to pull half the front out in a few months to do the turbo kit so it would be easier to do the radiator then since it hasnt cracked yet

sorry i don't know another source for the thermostat, hopefully someone else will be able to help you there. but iirc shipping didn't take too long, just like a week or 2.

anyway here's the page for the thermostat and radiator cooling panel / cowl cover fyi

http://www.trackdogracing.com/website/cooling.htm

there are cheaper options for the cowl cover, eg a genuine mazda one from mx5parts. they are really cheap, but you might already have one anyway? most of the na8's seem to have them already.

d-mag wrote: By the time I get home after driving nearly one kilometer up the dirt road in first gear, the car is over heating (can hear the water boiling).
The cooling system was flushed no more than 2-3 months ago.

Does the temp guage move, or does it stay just right of center? I always thought that the bubbling sound is just the coolant expanding into the overflow tank, and therefore is not a problem as such.

When I did the driver training day at Winton last Feb I could not do more than 3-4 laps before the temp guage had moved into the high range, mind you it was a 40c day. At that time I had a intercooler that was bigger than the radiator, in addition the under engine tray had been removed. I have since put a smaller intercooler in, put the under engine tray back in and installed a plate in the gap between nose and the radiator to ensure as much air as possible flows through the radiator. I should add that I have had a PWR radiator in the car since I owned her.

As per the following link, if you have the 2nd radiator fan you can rewire it to come on at the same time as the mainfan without the aircond having to be on.
http://www.miata.net/garage/parallel_fan.html

J

I'll stick a stock replacement from Repco in it tomorrow, but I'll order the TrackDog one and put that in when the alloy radiator etc go in, then keep the repco one as a spare

whats so good about the TrackDog thermostat?

AZNTieN wrote:whats so good about the TrackDog thermostat?

it opens at a lower temp , therefore allows coolant to flow earlier , thus preventing overheating, i guess

i dunno, it was cheap, i was overheating and i needed a new thermostat anyway. i haven't overheated since i fitted it so i guess it's working just fine !

Glad you're getting a new rad, I know a few turbo MX-5s that have kept the old radiator to save money or weight and have ended up doing damage.

You can wire it up so that both fans work, some suggest you need to put a relay in as not to overload the original single fan circuit.