my car will overheat when i let it idle. it does this only when the car is parked and running. is there any way to remedy this? what could the problem be?

 

Checked your coolant level?

 

yes, i check my coolant level almost every time i park my car at night jsut to make sure that the level is good. it has not dropped to the point where the light should come on. i do not see ANY coolant on my driveway either

 

Check your radiator cap to insure its holding proper pressure. After i changed my radiator i discovered my cap was bad. I'd let the car idle and the temp would shoot up. I'd say if you've checked everything and you still have the proper amount of coolant thats what it is.

 

isn't there a pressure rating on all caps? what should the pressure rating be for an 87 t2?

 

pressure rating should be on the cap, but just in case ...

check www.mazdatrix.com or www.rx7.com

i can't remember which, but one of them has a tech section that gives some pretty good guidelines for maintaining a good hi-po cooling system.

hope this helps you out some.

 

oh yeah ... also ... check the fan

 

There can be a pressure rating on a cap, and it can still be bad. The stock pressure on OEM caps is like 12-14lbs IIRC. It sounds like your fan clutch is going bad if you have a stock fan still. Turn it by hand when the radiator has been warmed up by driving, and it should offer a good amount of resistence. If not, then pick up another one. If it seems good, then check/replace your cap with a Mazda radiator cap, not some crappy Stant cap or the likes.

 

i have an electric fan. so is there any way to actually test a cap or is my only option to replace it?

 

I got the Greddy radiator cap from www.rx7.com. It raises the boiling point of the coolant by raising the pressure slightly. I think its rated at 19 psi, but i'm not entirely sure. there not that expensive, and are a quality piece. Stant Sucks. thermostats and radiator caps.

 

Which electric fan? Is it shrouded? Is all the plastic shielding in place?
How old is everything(cooling system parts)?
Is the fan running as the car overheats?

 

fan.

 

thermostat or fan

 

Put the factory fan back on and see what happens.

 

for peace of mind and the sake of your motor ... just replace it, they're not THAT expensive.

 

i am nto sure what kind of electric fan, it was up there when i got the car. no names on it to be seen. the shrouds are there. and the fan is wired up to run constantly (i am in teh process of figuring out how to wire it up correctly)

 

You solved your own problem. Did the seller tell you about the e-fan?
If it is only overheating at still/idle, then it is not moving enough air.
Either hit the recycle yard and get the mech fan/clutch/shroud or get a better E-fan.

Measure the fan. It needs to be about 16".
Measure the current draw of the fan with an ammeter. If it is not at least 10+ amps, then it is a low output cheesy fan.

I believe that the rotary(?) needs at least 2500-3000+ cfm.

http://www.flex-a-lite.com/auto/blackmag.htm
http://www.permacool.com/Catalog/Cat_page16.html
http://www.unorthodoxracing.com/projrx7.html

 

alright, i will try the fan first. if i end up replacing it, are there any suggestions as to which one to get? i have heard foor things abaou FAL fans.

 

My GXL is running very hot now too !!!! I put in a stant thermostat and cap . Im off to th emazda dealer to get the correct ones today . I dont want to ruin my motor . Im also running the balck magic efan .

 

Also, try flushing you radiator, go to a near by parts store, they should have some stuff you can buy and at the same time buy some good antifreeze. That helped out my last car. It was overheating only when the A/C was on and sitting in traffic. I looked at all the cooling stuff and everything was fine. Did that and not only did it not overheat but afterwards it ran a lot cooler.

kleach