I'm from Malaysia and have been driving an 1993 rx-7 FD3s since last year

at first i thought the car would be realiable enough for everyday drive but soon OVERHEATING and it has been a disaster even since, the average temperature is an average of 30C or 80+F all year round driving at noon or in the afternoon is total NO

just wondering if anyone has any advice or anyone from a tropical weather location might give some advice!

 

I live on the Southern gulf cost of Florida and it also has a very tropical climate. I don't have any overheating problems, but if I did, then I would either install a Miata thermoswitch or do the fan mod. The Miata thermoswitch causes the fans to turn on at a lower temperature. The fan mod can either turn on the fans at the push of a button, or can cause them to run all the time. Also, my coolant to water ratio is 35% coolant (antifreeze) and 65% water. The only purpose of the coolant is to help prevent corrosion in the cooling system. Coolant also raises the boiling point of your coolant, so it does not boil as easily. The only problem with coolant is that it does not cool as well as water. You shouldn't use less than 30% coolant, and ONLY use distilled (100% purified) water. If you can get Evans NPG+ coolant, then you can also try that. I think Evans NPG+ coolant requires no water and you don't need to flush your coolant every year and half. Oh yeah, you should flush your coolant (replace) AT LEAST every two years, NO MORE! Every year or year and a half is better. If you have lots of power modifications, then you should upgrade your radiator.


BTW, are you a native English speaker?

 

Best advice?
Upgrade your radiator and oil coolers, use water wetter, and install a cooler thermostat.

Since it's hot there, you probably usually use your AC. Meaning your fans are constantly on anyways, but you can always rig the fans to come on at full speed no matter what the temperature.

I can't find the site, but I'm sure someone here knows it. It's a site that explains how to rig the fans to always be on full speed. Most people wouln't recommened this, though, since the engine will take longer to warm up. Then again, you ARE always in a hot climate.

 

hey JONSKI, do you know exactly how much coolent/water the cooling system holds...i want to flush my system and put 35% coolent and 65% water as well but i dont know how to measure how much of each to put in.

P.S. I am also in Flordia but on the oppsite coast as you are

 

use a 80:20 water:coolant ratio, seem to work better in hot/tropical enviorments.

 

Only about a gallon of coolant comes out if you simply remove the radiator drain plug, but there is still plenty of coolant in the engine. What I did was this:

Drain the radiator once with the TB (Throttle Body) coolant hose off
refill with just distilled water
reconnect the TB hose - DON'T FORGET LIKE ME! (pic1, pic2)
run the engine until the thermostat opens
disconnect TB hose
drain coolant again
refill system with 35% coolant and 65% water
reconnect the TB hose
back the car onto an incline with the front of the car as the highest point
add coolant light should come on
refill system with more 35/65 coolant mix
you should now be all set


I bought a plastic 2-cup measuring cup. It makes it easy to mix and pour.

Please take your used coolant to a recycling facility. Don't leave the coolant sit anywhere animals can get to it. They love the taste and will drink it and die if they can get to it. (pic)

 

Just install a new thermostat, flush coolant I run 80%water 20% coolant with redline. Upgrade the rad (stock rad is too thin) seal around the radiator and oil coolers and temps will drop.

 

I forgot the address for the fan switch how-to, but if you do a Yahoo search for "lightning thunder RX-7" it will be number one on the list. The miata thermoswitch mod is better anyway. Also, Evans coolant can be used for the life of the car (500,000 mi.) but you need to be very careful about swithching to this stuff as it is not compatible with most other coolants or water. It is supposedly awesome though because it will never boil over on you and will never become corrosive. It's like 30 bucks a gallon.

 

forgot to mention, I live in St. Louis and it is extremely hot and muggy in the summertime. I am guessing the weather is similar or worse over there, so make sure you do something about the cooling system. You cant go wrong w/ a good radiator. I made the mistake of driving my car like a Honda the first summer I had it and am currently reaping the benefits. The car has been in the driveway for 3 months waiting for a new engine.

 

Two fan mods:
http://www.scuderiaciriani.com/rx7/fan_mod.html
http://rx7.voodoobox.net/

Radiator duct panels:
http://www.iluvmyrx7.com/

Good luck!

 

I went through my first Phoenix summer (115F daily hight for about a month) last year and here are my observations. While the A/C does turn on the fans, the condensor heats up which in turn feeds hot air to the radiator so the cooling isnt as effective. My temps always go up by about 10C when I have the A/C on and am not driving at highway speeds. As long as temps are below 100C I dont worry at all, between 100 and 110 I keep a close eye and if they get over 110 I turn the heater on. It only takes a few minutes to get the temp back to 100. Really sucks driving in 115 heat with your heater on but it is better than buying a new engine. On the open road the temps stay about 87-90C even on the hottest of days with the A/C on.

My cooling system is as follows:
Koyo radiator
Evans coolant
0 pressure system
new thermostat (Mazda, dont get aftermarket)
new hoses
metal tape directing air into radiator from mouth of bumper
PowerFC set for high fan speed at 90C (I think that is what I put it to)
down pipe
high flow cat and cat-back exhaust
dual oil coolers (I have an R1)

 

I survived houston's summer (2002) on stock everything except aluminum AST. I did have fresh coolant 45/55 regular green stuff. I drove it everyday to work with a/c on with no probs. In August my stock radiator started to leak and I now have the mazda comp unit.

I have a lot of mods now so we'll see how it holds up this summer.

 

Been through a couple of Texas summers on nothing but an upgraded radiator without any major problems ... at least, overheating-wise . When I first bought the car, the top tanks on the stock radiator cracked within a month. Typical for the cheap stock radiator .... bite the bullet and upgrade to a Fluidyne or Koyo radiator and you shouldn't have this complaint anymore. But, watch out for the radiator/AST hoses as they do tend to get old and worn over time. They rot from the inside, so it's difficult to evaluate them without pulling them off. But, it's in your best interests to replace them when you upgrade your radiator anyhow.

 

I'm in the virgin islands with the same climate year round and steep hills ,my car runs cool stock cooling system with distilled water on a modded engine.