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Joes924Racer

Im going to dual fans and since itsgoing turbo in time ( I have to
check out and clean up the motor ), its only fitting the
the thermo switch work like it should. I used to run with a on -
off switch on the dash (or the fly). Now in the future I dont want
to have to stay around to man the dash switch to shut it off
after cool down.

I have the wires & complete set up for the dual fans i just need to know
how to get power to them ...
Can I just splice it in to a power wire.

What temp. by the way is the switch activated to power the fans.
its probly in the tech. data somewhere. Need some help here..
so let me know.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Joes924Racer · Posted: Thu Jun 17, 2010 7:44 am Post subject:

I know its an easy common sence question..but no takers
com-on.. give a DIY solution. Im switchin over the engine
harnesses when the turbo motor goes in, hopefully the plugs are
the same and everything has power though .. id still like an answer.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Ozzie · Posted: Thu Jun 17, 2010 8:49 am Post subject:

give it time.
Not all of us are awake the same time as you.

I am not up to speed on the dual fan setup.
The single fan setup has a resistor and relay in the circuit.
The fan switch on the rad can be whatever temp people buy but usually 87C.
I rigged two fans in my car, one in front and one behind the rad.

One fan runs with ign on.
Other runs as per the Haynes.
If temp switch activates:
ign on- full speed
ign off - slow speed.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

leadfoot · Posted: Thu Jun 17, 2010 9:02 pm Post subject:

you can get circuit diagrams from the pelican website...
IIRC there are two control cicuits

battery - fuse - relay ....

1. control line to relay run through ignition and earthed through the thermo switch.
2. run from battery to fuse then resistor and earthed through TTS.

ergo, when ignition on, normal operation and when the TTS earths the fans come on...
when ignition off, slow running speed via resistor limiting power draw from the circuit.

there are also cooler 83Celcius TTS if your car tends to see really hot weather.
Stu
P.S I am rarley awake at 2.53am on a Thusrday morning....
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Rich H · Posted: Thu Jun 17, 2010 9:16 pm Post subject:

It's not the TTS - it's jsut a thermal switch , TTS is part of cold start.

Personally if I were going that route, I'd have one fan wired as normal and one on an override. That way if you get stuck in traffic or after a high speed run you can start extra cooling immediately without having to wait for the system to get hot.
_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

leadfoot · Posted: Sat Jun 19, 2010 3:22 pm Post subject:

yes yes yes , thermostat to be correct, talk about picky...

if your car is stuck in traffic and overheating there is something definately wrong with it.

if the engine is on and coolant circulating and it overheats there is something wrong with it, either blocked air, or passageways, radiator etc...
it should be sitting on the half way point on the gauge and only go into 3/4 or red momentarilry... period

the only exception I can see to this is tuning the engine temperature to the optimum fuel burn as per octane spec and air fuel ratios... yes, we all go to this length in setting up coolant temps... lol

you can also use lower temp thermostat in the radiator as well as the front of the head (87C or 83C) I did this and it was very beneficial.

The biggest problem is after shutdown. mainly in air co setups because the heat exchanger was jammed infront of the radiator and poor circulation causing undue heat soak in the oil and back of the head.
I rectified this by;
changing both fans to run off ECU, 83C, and running directly off a relay from direct battery source.
also modifying the cossover pipe and bypassing running through the heater unit is a bonus.

Another way is to use electic water pump and modify the line to suit AKA GTR style which changes the direction of flow through the head.
There are lots of posts documenting this.
Stu
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

9XX Girl! · Posted: Sun Jun 20, 2010 8:29 pm Post subject:

Joes924Racer · Posted: Mon Jun 21, 2010 2:40 am Post subject:

So if its wired correctly I can jump the poles at the sensor in the rad
& the fans should start with ign on. Then the reistor for when its off
for slower cooling.

_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Joes924Racer · Posted: Tue Jan 04, 2011 12:20 pm Post subject:

Seems to work like it should it goes on and off
at a good temp... need to test more..
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Joes924Racer · Posted: Wed Jan 05, 2011 5:01 am Post subject:

Getting temp readings hovering at 185 degrees F.
after numerous tests of operating temps.c Thatll
fly wont it.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.