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Discussion Starter #1
Question as I took apart my a/c system to dissasemble my motor I was wondering will the aux. fan on the a/c condensor work as an electric fan for the radiator and thereby allow me to not put the belt driven fan back on( yes I would still need belt for water pump so not saving "hp" just cleaning up engine bay). Or would it be good to add to the front of the radiator with a switch inside to use in case of stop n go taffic on hot day etc. Just thinking out loud as I'm considering not putting a/c back in.
 

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Question as I took apart my a/c system to dissasemble my motor I was wondering will the aux. fan on the a/c condensor work as an electric fan for the radiator and thereby allow me to not put the belt driven fan back on( yes I would still need belt for water pump so not saving "hp" just cleaning up engine bay). Or would it be good to add to the front of the radiator with a switch inside to use in case of stop n go taffic on hot day etc. Just thinking out loud as I'm considering not putting a/c back in.
Yep. It's done all the time, in fact. If you're keeping your air-conditioner you'll need to keep the front mounted fan and add a secondary "puller" fan to the radiator. A 10in fan, offset a bit, should do the job. There are a lot of kits avaliable to do this.
 

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If I put the a/c back in I would just use the regular fan, not looking to spend more money, just thought if the aux fan was big enough could I use it alone and not put the fan back on. Would the temp switch as used to turn on the fan for a/c, work to turn on fan for radiator if wired correctly so it would be powered/ come on with ignition not just if a/c switch was on and does it only let a/c fan come on if temp is higher than normal operating temps are reached?? I think I'll do this and not put the fan on. It would make belt changes/ timing checks etc. easier.
 

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Would the temp switch as used to turn on the fan for a/c, work to turn on fan for radiator if wired correctly so it would be powered/ come on with ignition not just if a/c switch was on and does it only let a/c fan come on if temp is higher than normal operating temps are reached?? I think I'll do this and not put the fan on.
The temp sensor can and does operate the fan regardless of the AC or key position.
If it senses too much heat in the shroud area, it'll kick on the fan regardless of anything else.

Likely you'll want a programmable snesor to replace the one that's there already. For one, it'll ensure a new part that's less likely to just **** the bed like a 20 odd year old part could at any moment, and two, with adjustability comes the ability to dial in the activation and deactivation temps you want, not what a fixed sensor decides you're going to get, even if it is 50 degrees too hot or too cold.

If you wanted to get a bit redundant, leave the temp sesnor portion of things alone and fit in a toggle switch in place of the AC switch so that you can turn the fan on manually should you feel the need or the sensor fails.
Might never actually use it, but it might also be the only thing between driving home or a tow truck.

In regard to the use of the 'stock' AC aux fan for sole cooling purposes, I'm not all that convinced it moves enough CFM to do the job.
I've been looking for specs for a long time on that specific item, but have never actually found what they push.
That being said, there's a sort of unspoken concensus that you'll need around 1200~1300 CFM at minimum, and preferably closer to 1500 CFM to get the job done efficiently.
Some have accomplished it with one big fan, others with two smaller fans that when added together create enough CFM flow.

Pullers seem to be favored slightly more than pushers as the puller stops air in the core itself where it has time to convect more heat to said air, while pushers will sorta prevent air from getting to the core and thus only really cool effectively when the fan is on.
EG: a pusher setup might run at the same temp as a puller, but 'could' be subect to more frequent fan activations due to the lesser amount of air on the core at a given time, so things heat up more rapidly.


The above is not the absolute gospel, just what I've picked up here in the forum and other places over a period of time so YMMV along with opinions and infobits presented by others.
 

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Discussion Starter #5
That's what I was afraid of I did not know if it had the capacity to keep things cool on its own. There does seem to be a lot more air that can flow through without the condensor being there so I thought that might help. If nothing else i'll put it on the front of the radiator and let it do its thing with the stock fan. Just thought it was a waste to set it aside just cuse I didnt want to put the a/c back in yet. All opinions or prior experiences are appreciated.
 

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I had only a single electric pusher fan on my '73 GTV with AC, but GTV's have better airflow to the radiator than Spiders. I run my 79 Spider which does not have AC with a single pusher fan that seems to be stronger than the one that was in the GTV. I live in Columbia SC. It gets hot here in the summer and my pusher fans work fine. I think that there is little difference if the fan obstruction is right in front of the radiator or right behind it. I like all the extra space that I have in front of my engine without the fan plus the extra ~7 HP at 7000 rpm.
 

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I had only a single electric pusher fan on my '73 GTV with AC, but GTV's have better airflow to the radiator than Spiders. I run my 79 Spider which does not have AC with a single pusher fan that seems to be stronger than the one that was in the GTV. I live in Columbia SC. It gets hot here in the summer and my pusher fans work fine. I think that there is little difference if the fan obstruction is right in front of the radiator or right behind it. I like all the extra space that I have in front of my engine without the fan plus the extra ~7 HP at 7000 rpm.
Is your pusher stock for the radiator or was it an aftermarket radiator fan Just wanting to know if there is a diff in the flow of the stock a/c pusher fan V the flow from a true pusher radiator fan. I figure you can get different cfm fans aftermarket and did not know where my a/c fit in the mix. Tifosi's reply described my quandry in not knowing what the CFM's were of the stock a/c fan to compare to aftermarket. I do not want to buy any thing just want to make good use of what I have. I can say there is a lot of space in front of the rad. now with out the a/c condensor there just not a huge opening at the grill. Maybe someone has actually tried the a/c fan and can report their results or failure with it.
 

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I have a small Toyota, Corolla sort of fan pushing air in my Spider. Seems to work fine.

Had to fabricate brackets to hold it securely in place. It is using a VW temp switch which just happens to fit the lower driver's side plug in the radiator like it was made for an Alfa.
 

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I bought a curved blade type fan on ebay. It looks like the one in the Centerline catalog. I attached it to the radiator using plastic cable ties. I once made brackets and attached the fan to the cowl under the front of the car but it was a bad idea. It was noisy as hell and a good amount of air went around instead of through the radiator.

I use a capillary bulb type temperature switch that was about $20 from O'Reilly parts. I had bad luck with the screw in types that go into the bottom tank. Two of them failed open circuit and I only found out when the engine started to run hot.
 

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I've been looking into using the curved bracket from an old aux AC fan to install a new electric fan; I'd like to grind off the rust and repaint it, but I can't figure out how to remove the rubber grommets (through which the bolts pass that hold the fan in place). They appear to be one piece and the grommet collar seems to be too wide to fit through the hole in the metal frame. How did they insert these things in the first place?
 

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They appear to be one piece and the grommet collar seems to be too wide to fit through the hole in the metal frame. How did they insert these things in the first place?
Like a windshield gasket: put a string in the groove of the rubber, then feed the string ends through the hole of the frame, get a corner of the rubber over the lip of the frame, then use the string to pull the rest of the rubber over the edge of the lip.

Or, you could fight it with screwdrivers like putting a tire onto a rim.

Taking the old ones out is just a matter of getting an outer edge on one side rolled/pulled/levered back enough to get it disengaged from the edge of the hole, then using that slack to kinda roll/tweak/twist the remainder the rest of the way off.

Or you could just cut a radial slit in the rubber on both sides of one side of the bracket and fold it to get it out of there. :shrug:
 
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