Auto Elec Help Wanted
Thread Starter
Racer
Joined: Dec 2003
Posts: 313
Likes: 1
From: Sydney, Australia
Auto Elec Help Wanted
Does anyone know how I can modify my early '85 car to make the low speed fan run whenever the ignition is ON/car is running.
I live in a warm/hot climate and the fans cycle on/off about 5-6 times on a daily 15KM commute in heavy traffic. Having the low speed fan run all the time would elininate this. Does anyone have any ideas on how I could do this do this.
I live in a warm/hot climate and the fans cycle on/off about 5-6 times on a daily 15KM commute in heavy traffic. Having the low speed fan run all the time would elininate this. Does anyone have any ideas on how I could do this do this.
Hey Man
Rennlist Member
Rennlist Member
Joined: Jul 2003
Posts: 16,547
Likes: 199
From: Nor Cal, Seal Rock, OR
Does your car have the older 3-blade fans? If so a swap out to the later 6-blade set up is a great improvement...runs less and is so much quiter. I did this to my 83 and feel it's one of the best things you can do to reduce the constant cycling of the older fan set up.
Drifting
Joined: Aug 2002
Posts: 3,224
Likes: 1
From: Eastern CT
When you turn on the AC, both fans should come on and stay on at high speed. The AC relay bypasses the thermo switch on the radiator. If you are not using the AC, then you can purchase a lower temp thermo switch for the radiator which should accomplish what you want. The low speed fan only runs with the ignition off if things are still hot enough at shutdown. I posted the schematic of the early 944 cooling wiring a month or two ago. A search should dig it up.
Thread Starter
Racer
Joined: Dec 2003
Posts: 313
Likes: 1
From: Sydney, Australia
Iv'e considered the 6 blade fans and the lower temp thermo switch but these would only result in either the temp coming down faster once it gets hot or the fans coming on earlier or a combination of both. If I could make the slow speed fan run all the time the temp should stay in the low zone. The adjustable fan controller seems like a good idea though.
Surely some of you auto elec wizards can advise a wiring mod that will make the slow fan run when the ignition is on.
Surely some of you auto elec wizards can advise a wiring mod that will make the slow fan run when the ignition is on.
Race Car
Joined: Jun 2002
Posts: 3,781
Likes: 0
From: Costa Mesa, California
The different speeds that the later fans run at are controlled by the two element radiator temp switch, some hefty ballast resistors behind the glove box and the $150 extra large silver relay in the fuse box.
You could use the two element radiator temp switch and another early radiator relay with the later six blade dual fan set to turn one fan on at lower temps and the second as the temp climbs higher. I've been considering this.
In any case I strongly recommend getting a pair of the later six blade fans for your car. These have better motors in them with sealed bearings and conventional brush configurations.
However as was suggested above you could replace the stock fan(s) with a newer unit with several speeds. Just need to get the units temp sensor in the right place.
You could use the two element radiator temp switch and another early radiator relay with the later six blade dual fan set to turn one fan on at lower temps and the second as the temp climbs higher. I've been considering this.
In any case I strongly recommend getting a pair of the later six blade fans for your car. These have better motors in them with sealed bearings and conventional brush configurations.
However as was suggested above you could replace the stock fan(s) with a newer unit with several speeds. Just need to get the units temp sensor in the right place.
