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Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Ok, i finished the coolant thing.. Finally. Thanks rasta Paul etc all those who helped. But now my rad fans won't work, or come on.. AGIAN, I just replaced these things!! There not new new but new used and were workign when i put them in. Did the coolant thing and now they don't work agian. Tried AC testing and just letting car get hot and nothing.. What 'cause rad fans to blow on after the other?
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Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

JayZzzz4 · Joined: 23 Sep 2008 Posts: 544 Location: Milwaukee, WI USA

Could it be a bad fuse? Or maybe your temperature sensor is bad. Maybe test your fan with a battery to see if your fan motors are ok.
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White 1987 Porsche 924S manual

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Like I said, when i first put them in iturned the AC on all the way (kicks the fans on) and they worked.. So i dont think its a fuse. And now they don't.. I've been messing with bleeding my coolant system (still unsuccessful) maybe I just shorted 'em agian? I just refuse to believe my luck is that bad. Why don't they make the stupid things water proof? I'm not gonna be buying rad fans everytime i wanna go driving in a light rain.. Help plz?
an p.s. , if it is just my awful bad luck that did it, can someone recommend WATER PROOF rad fans that will fit in it?
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

924RACR · Posted: Sat Feb 14, 2009 3:00 am Post subject:

Relay maybe? Sounds like you need to try using your voltmeter on the wiring instead of just swapping parts...
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Im voltmeter / car electronic retarded.. I used to have a elec tech kid come up here and check my stuff for me but we don't talk any more so I'm screwed in that department.. So even if they worked 1st off when i did they AC test, and don't now, still means it could be a relay?
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

It's most likely the fan switch, which is a big screw in (34mm IIRC) sensor with two leads that plugs into the upper left corner of the radiator. It's possible that the AC relay could be an issue, but given everything else you've been thru, I would suspect the fan switch first.
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erstwhile owner of just about every 924 variant ever made

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

Not the thermofan switch if the fans do not turn on when you switch on the ac system.

There are two relays that three relays that affect the cooling fans. #1 is the cooling fan relay, #2 is the ac relay, and #3 is the cooling fan interlock relay.

The cooling fans are supposed to turn at high speed any time you turn on the ac system, regardless of the coolant temperature. If they don't, you have a problem with the wiring, the cooling fans, the ac relay or the cooling fan interlock relay.

If you are ever driving and the cooling fans fail to turn on when the coolant is hot, then the thermofan switch has failed, or the cooling fan switch has failed, and you should be able to force the cooling fans on be switching on the ac system (if there is nothing wrong with the ac and interlock relays).

If the fans do not switch on no-matter what you try (coolant hot, and the ac trick fails), then you probably have a problem with a fuse or the wiring or the fans themselves.

If the cooling fans run at low speed with the ignition on and the coolant hot, but not the high speed, then the cooling fan relay is bad.

If the cooling fans do not run at the low speed with the coolant hot and the ignition off, then the low speed resistor or the wiring for it is bad.

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

hmm.. i thought it could be too but they worked before thats whats throwin me off! i guess i'll just buy a relay AND the switch.. thanks guys.
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Thanks for all yer help guys, like i said i guess i'll just buy all new relays and thermo switch..i don't have near the money cause relays are expensive but maybe in a couple months i'll be able to live my life agian.. This sucks. Just one thing after another.
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Oh and P.s. when i turned on the AC before my fans came on with it, now it dosn't. They never came on when the car got hot tho.. so maybe it is JUST the switch? But if it is why don't they work with the AC test this time? It canbt be the AC fuse cause when i turn it on it makes noises like fans are on, but i do not see the rad fins spinning.. still confused if anyone wants to give some input on that.
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

CorsePerVita · Joined: 25 Jul 2008 Posts: 1992 Location: Redmond, Oregon

I would highly suggest to learn to use a voltmeter where you are in the automotive hobby. "i'm voltmeter and wiring retarded" is more of an excuse of "I don't feel like learning that." and throwing money at parts can fix things (eventually) but you will learn more in the process of doing this stuff if you do the troubleshooting to get to the core problem and in the end save yourself a lot of money.

Here are some wonderful resources on how to get into the basics:

http://www.electrical-online.com/doityourselfrepairsarticles.htm
http://www.the12volt.com/Default.asp?
http://www.mmxpress.com/technical/
http://www.ehow.com/how_16767_voltmeter.html
http://www.howstuffworks.com/question501.htm

Now you have some basic articles and wonderful bits of information to work with

May your adventures go well with wiring. It's not as hard as it seems, just requires patience to understand.

Hope this helps

Good luck with your car.
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- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Thanks alot for the guide lines man, i'm deff gonna read up on that tom. I did the ohm test wit hit cold, and with it hot. (on the temp switch it read infity each time so im guessing thats also shot.. I wouldn't doubt 2 of those 3 relays are bad either tho.. Knowing my luck. Like when i try to tur the AC on its like the car wants to turn it on and its on in the car but the rad fans dont go.. So weird.
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

!tom · Posted: Sat Feb 14, 2009 10:25 am Post subject:

The easiest way to eliminate the thermo switch as the culprit (even easier than using a meter, because you have to heat the car up to do that) is to bypass the switch and see if the fans turn on.

Just short the two leads on the switch together with a piece of jumper wire. If the fans turn on when shorted and off when not shorted, then the problem is the switch. If they don't turn on, then you have a problem elsewhere.

This test doesn't tell you if your switch is good, but that's not what you're interested in. This will tell you if replacing the switch will solve your problem, which is what you're interested in.

As far as the piece of wire, heck, you could even use a screwdriver, if you are severely lacking what it takes to maintain these cars.
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78 924 NA
5-lug

Boostsideways · Joined: 11 Feb 2009 Posts: 100 Location: CT, Southbury

Im not (except any Porsche tool =p) i have a big garage full of useful things, like jumper wire. thanks alot for the tip man i'll try that tom!
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.