lzamboni

iTrader: (8)

Hi all, its been a while since I posted something here. Too much work
Anyway, the thing I wanted to ask now was if it was normal for a FD to stop the electric fans after turning the engine off, or like some other cars they should keep going for a while after stopping the engine?
I am asking the question because if I turn the engine off and the start the car after let say 5 minutes, the temperature is at 230 degrees ( I know it is normal for the temperature to raise but is it 230 a little too high?) but after that it drops very fast to the normal 190 degrees.
And since I have some kind of electrical problem in the car that is causing all kinds of weird little things to happen, I just wanted to make sure it was normal operation for this car.
Thanks for the help...
Leo

DaveW

230F is about right if you still have the stock thermoswitch (doesn't turn on the fans until ~220F under normal conditions).

rexhvn

Heat soak.

rotarymandan

iTrader: (15)

You could do the FC thermoswitch mod:
https://www.rx7club.com/showthread.p...t=thermoswitch

lzamboni

iTrader: (8)

Thank you all for the answers, but I think that maybe I didnt explain myself too clearly.
While the engine is running, I dont have any problems, the temperature never passes over 190. I have an Apexi PFC commander and I dont know if that is controlling the fans but, lets say I stop the engine but keep the key in the ignition on position, the fans keep working and keeping the temperature from raising above 200.
But if I take the key out of the ignition, then the fans stop and the temperature goes to 230. And of course from there it starts cooling down very slowly like any other engine.
What I was wondering was if the fans should stay on after the engine is off for a while to keep the temperature from raising?
Thank you all...
Leo

juha kankoulen

........newer FD versions allow the fans to work even if you pull the key from the ignition..........I suppose that gives you a clue of what you should do

..........you can control the temperature in which the fans engage by your PFC (ask your tuner about it)

Mahjik

iTrader: (1)

There was a cooling system recall that was done to the cars to run the fans after shutdown. More information on it here:

http://www.fd3s.net/fan_circuit.html

What production year is your RX7?

jmadams74

With a stock thermoswitch, the fans will run for 10 min after shutdown if the temperature has been above 108C for 2 minutes prior to shutdown. If you replace the stock thermoswitch with the FC 95C thermoswitch, the same is true except the temperature measurement is 95C instead of 108C. As (or more) importantly, with the FC thermswitch, the fans will go into high speed at 95C instead of 108C. This "high speed" function is not and cannot be controlled by the PFC.
--Jeff

vrmmmpshhh

instead of making a new thread, can i ask any of you fan gurus how to wire up the fans so that i can flick a switch and have high speed instantly so when i hit traffic i wont have to worry about raising temps. Summer is coming and it gets VERY hot here.

jmadams74

http://www.fd3s.net/fan_mod.html
see 3rd gen FAQ

adam c

iTrader: (2)

I have used the fan mod listed above for many years. Definitely a good mod!!!There is a 2 minute delay before they come on.

I always use the switch when driving in town, and always turn it on several minutes before I reach my destination. I like to have the fans come on early to cool the engine to 180 before I shut it down. This reduces under hood temps after shutdown, which should prolong the life of all the rubber and plastic components in the engine bay.

vrmmmpshhh

my car is a jap model 95. I have tried the mod but it doesnt seem to work on mine. i think id rather a switch to turn the fans to full blast when needed. That way i can control them.

lzamboni

iTrader: (8)

Hi all again, my RX7 is a '93. And it looks like the PFC may be programmed to start the fans early since the temperature stays constantly at 180 to 190 degrees. After I stop the engine, if I keep the ignition on, the fans stay running and keeping the temperature between 190 and 200 degrees and it doesnt go up.
But the problem is if I take the key off the ignition. Thats when the fans shut off and the temperature rises. It may be something related to the alarm too?? Because it has a turbo timer and when I turn the engine off, the timer keeps it running for around 3 minutes, UNLESS I go out of the car and shut down the door, then the alarm connects and the engine shuts off immediately no matter if only 20 seconds have passed after taking the key off the ignition.
Well, I will try to do the switch trick and if it doesnt work I guess I will have to get this car to an electrician or someone knowledgeable in alarm systems.
Thanks to all for the help.
Leo

FD3S2005

iTrader: (11)

I'm in the same boat as u lzamboni..wish i could make my fans keep going for a lil after i turn it off... thats what i use my Turbo timer for tho.. just to keep the electrical on and the fan running for a lil bit and the temps do go up a little with the hood up and a fan blowing into the bumper, but then i start it after about 4-5 mins of sitting with the fans and keep it running for 10 -15 seconds to bring it down then and circulate the hot coolant with the cold and turn it off.. but this is when I'm home and putting it in my garage if I'm out somewhere i dont do this..

forgot to add i do have a pfc tuned by steve kan and he also ajusted it to turn on while driving at 85c which is 1585F. he does it to all the cars he tunes

Maxrolla99

i kno exactly what your talking about. my car did (now blown engine) that EXACT same thing. i didnt pay any attention to it tho because once you take the key out the fans stop, so therefore the hot air just lounges around so the temp will rise. but once you turn the key the fans kick in and it slowly goes down. i wouldnt pay any attention to it. no big deal really.

beqa16v

FD3S2005

iTrader: (11)

who said a blown engine?

Maxrolla99

not because of that smartass

beqa16v

i know dude relax i quoted that for fan realy

Southwestspeed

I just use my turbo timer. Set the timer for how long you want the fans on after you turn off the engine.