Radiator and Cooling

[Sky]

Hi,

Over recent weeks I\'ve noticed that my FD tends to get rather hot at idle - that is, sitting on the drive it\'ll eventually cause the fans to kick in, go back down to 85 or so, fans kick out, up to fan-temp again and so on. I\'ve got an aftermarket water temp gauge, and an FC commander, so I can see what\'s going on easily enough.

I\'m fairly certain it didn\'t do this in the past (and it doesn\'t do it when the car\'s moving) so I was wondering what this could be. According to the cooling troubleshooting thing I\'ve got, most likely culprits are:

- thermostat
- radiator fins mashed by stones

I\'m not losing any coolant at all, so I\'m not worried about seals, and it doesn\'t get *that* hot before the fans whir into action, but I\'d like to get this fixed.  What sounds most likely?

I\'m also tempted, if it\'s going to have to go in to a garage anyway, to get an uprated radiator to replace the stock unit. Does anyone have any recommendations for a stock-mount radiator - what make,  where I should purchase one, and how much I should be looking at spending?

Any advice appreciated,

Rick

[MikeLMR]

I\'m not sure if this is true of the FD but that sounds perfectly normal. As long as it doesn\'t overheat and it doesn\'t run too hot on the road I wouldn\'t worry too much about it.

[Sky]

I\'m not really too worried, but it didn\'t have this problem in the past and, what concerns me more, it\'s happened in really low ambient temps as well (4 degrees C ish) - I\'m wondering what\'ll happen in summer if it\'s doing this now.

Rick

[andyrose]

That sounds about right.
nearly all cars that just sit with the engine running will get to a stage where the temp rises enough for the fans to come on as your not getting any airflow thru the radiator.
Aslong as the fans kick in and the temp drops down i wouldn\'t worry too much about it.

my two pennies worth anyway

Andy

[Fish]

I have to ask this.

After taking the car for a good hard drive, do you let it cool down before switching the engine off?

During this cooling down time you should have the fans come on at least once!

But as already said, if a car is left at idle for a period of time the fans will kick in.

Fish

[Sky]

I\'m quite careful about letting it cool down - I guess I\'m lucky in that it takes me ten minutes or so to get to a fast road from home anyway, so it has that as off-boost cool-down time, then usually some time sitting on the drive as well.

Anyway, if the fans kick in for everyone else then I guess I must have just been remembering it wrong.

Thanks,

Rick

[antnicuk]

mine too,  so i shouldnt worry.

[scooby_si]

sounds similar although i havent had chance to study mine in any detail http://www.smileycentral.com/?partner=ZSzeb008\' target=\'_blank\'>http://smileys.smileycentral.com/cat/4/4_6_101v.gif\' border=0> but on a relative tangent what is considered too hot for water temps? Triple figures: more, less?
Si

[antnicuk]

i\'ve been told over 110 and you should turn it off!  anything over 100 and i wouldnt drive it hard until it had started to get some air through it to cool it down a little.

[Martin]

since you have a commander, maybe you should set the fans to come in earlier, as for a radiator you can order one from http://www.coolradiator.com/HPAMazdaRX7.htm

I have emailed them before and they will ship to the UK, and have 2 different shipping rates, also these are at least twice as think as the standard radiator. or try the other vendors here:)

[olly]

you should be worried if your fans don\'t kick in when sat at idle for some time.(the radiator needs air to be passed through it for the heat exchange to take place).