924Board.org

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

So i tried the AC test, I bought a new thermo switch, tryed bridging it, switching the connections.. the fans won't come on.. When i first got 'em i ran a split speaker wire from my car bat to each end of the fan inputs.. Did i just fry my fans Again and all this fus is about nothing? does anyone know a quick easy test i could do to see for sure whether i just messed up my fans again or if its the relays.. 'cause those are the only two things I can think of since the wiring looks fine.. p.s. won't turn on at all..
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

Ozzie · Posted: Thu Feb 19, 2009 7:12 am Post subject:

Put a meter on the leads on the thermo switch with ign on.
Is there 12v?
yes .. good.

No? fuses or relay.
I'm assuming the fans ran when you connected them to the battery and no it doesnt hurt them.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

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

No they didn't, they made a spark like they were about to turn on, but they never really did. I think it was cause i was just running the power through one.. i dunno tho.. Like i said when i did the first original AC test they popped on. and now they don't.. thats my biggest mystery.. Later today im goin' down to try that test posted above, even though i've already done a similar one were you test it cold in ohms then hot and look for zero instead of infinity... yer idea makes more sense to me tho =p. Thanks homie! =)
p.s. my thermo switch is brand new so it can't be that. just got it in yesterday =p
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

Smoothie · Posted: Fri Feb 20, 2009 3:01 am Post subject:

If you don't know much about electrics, it's best to test one at a time. Otherwise, testing them together, you might mistakenly wire them in series which would have only 6 volts going to each. Testing one at a time definitely supplies 12V (from a 12V battery). The OE factory wiring has them wired on seperate circuits, each with its' own fuse. For testing you don't have to be concerned about polarity. (+)to(+) and (-)to(-), or (+)to(-) and (-)to(+) - either way will make them run if they're OK. The wrong polarity would just make them run backwards, and won't hurt them. Obviously, they do need to be wired correctly for proper engine cooling eventually. Just verify that they blow toward the rear when everything's back in working order, and before driving around.
Worn-stuck bearings are not unusual with old 924 fans, so give 'em a spin by hand to check for that.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

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

On both my new fans and my old fans they spun hard, well one fan on the new rack spins Fairly easy by hand.. Did this guy sell me bad fans? and p.s. I volt tested at the thermo and it was going up and down up and down, whats that mean? bad relay im guessing? anyway to narrow it or do i just have to buy all three new relays?
p.s. do you know any sites where i can get all 3 relays working for cheap? thanks guys. =)
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

Ozzie · Posted: Fri Feb 20, 2009 7:00 am Post subject:

I would not buy any relays until you confirm your fans run.
Put 12V from the battery on them to test.
Fluctuating volts means you have a bad connection. I doubt it is a relay.
These cars are known for bad earths, fuse connections, plugs and wiring.

Relays are almost bullet proof but have been known to occasional fail.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

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

anywhere i should check in particular?
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

Ozzie · Posted: Fri Feb 20, 2009 1:00 pm Post subject:

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

I've done this with both them, my newest set sparked and looked like they wanted to turn, but pretty much the same happened with my old ones.. Wth? Did i just pay this guy for bad fans? Or do i need a 12v fuse laid in the line from the bat to my fans?
_________________
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

P.s. could this be my fan fuses? I've been reading up on random rad fan problems (none for my car but others) and it seems like people mention fuses alot.. is there any special fuses for each thing or can i just buy a bunch of new fuses and replace 'em all? I believe someone said since my thermo switch is getting volts (going crazy up and down up and down) he dosn't think it's my relays.. But the wiring looks fine.. Im stuck.. still.. any ideas?
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.

Smoothie · Posted: Sat Feb 21, 2009 1:16 am Post subject:

No, adding a fuse for your direct battery-to-fan testing won't make them run any better. A fuse is just a thin piece of metal that's sized to burn and open the circuit at/above a certain amperage. They're intended to protect the wiring from burning in case of a short circuit or overload.
From the apparent results of your testing, it is looking like you have a small pile of bad fans there.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

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

Lol smoothie I had a bad feeling this whole time... Rad fan BRAND NEW tho are freakin like 350 bucks a piece off any website i've looked at so far
( besides e-bay, but thats how i collected this pile of broken fans=p ) and im guessing the test to make sure is hooking them up to my bat? cause if thats the case i need all new fans.. suggestions on where to get 'em new for cheap? or maybe i can use a cheaper fan off a Audi or something maybe? Not willing to fabricate for it to fit tho.. Thanks team!
_________________
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

I think I might have an operational dual fan setup for a 924 which is available for sale, but I won't be able to verify what it's for or whether the fans are good until tomorrow.
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erstwhile owner of just about every 924 variant ever made

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

Oh sweet idea, ya i got my last set off ebay for 80 bucks.. wish the guy would have told me they were broken and saved me the time/money. But hey scammers gotta make their money some how.. bastards.. but anyway ya its a 924 turbo 1982 (obv), if ya think they'll fit and they actually fricken work drop me a price quote. thanks hommie =)
_________________
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

as p.s. anyway i might be able to take 'em apart and try cleanin' 'em up or something? i don't even see a section in my book for testing them let alone that..
_________________
Just wait 'till my turbo starts firin' the RPM LZR!
My car= Porsche 924 turbo, 1982.