davep_96

So right now my radiator fan is not wired to a temp switch/relay. When i switched engines i wired it to a switch located in the car because the relay was broke and the fan didnt turn on at all at the time. well now id like to rewire it so i dont have to control it in the car. Firts of all, would it hurt anything if i wired it so that the fan came on whenever the car is running? If its ok, then how would i go about doing so?

If it would hurt something, then id like to get a lower than stock temp relay for the fan. Once i get it how do i hook it up? I dont remember how the stock broken one was wired up.

Thanks ahead of time

camaronewbie

My suggestion would be an aftermarket fan controller. They are adjustable, reliable, easy to wire, and probe the radiator rather than tapping the head (no more coolant in the face replacing factory type fan switches).

I use a Flex-a-lite model from summit. It's totally adjustable temp wise, has provisions for dual fans and A/C (so that the fan runs always with A/C on), has wiring options for manual in-cabin switch to override the temp sensor (turn on when you want), and I've had mine 3+ years now without any issues at all. Bypasses the relay, the factory in-head fan switch, etc. and does it all itself. Very easy instructions - I had mine wired in an hour!

There are other brands, with different bells and whistles, some more, some less - but you get the idea - and they work with any fan! Think the model I got was $70, and well worth every penny! IMO It's a great upgrade over the stock fan switch/relay junk that always seems to give everyone problems.

henryd3

iTrader: (128)

Check this out. It's got stuff camaronewbie just mentioned as well as original specs if you have the single fan. Right under it in the technical articles section are the specs for dual fans. Be cool!

https://www.thirdgen.org/electric_co...pec_mod_single

camaronewbie

A few other thoughts -

1) if you have a stock single fan, the cfm on it is about 1200 (according to the ratings on a Autozone replacement). For $100, a replacement fan of the same size, but 2x the output can be had aftermarket. This is my next step, as my 350 seems to run hot and doesn't like it.

2) I noticed that, with the single fan anyway, there is no shroud. The fan just mounts and sits in front of the radiator. This means that the 'pulling cool air action' is only happening within that 16in of space - the radiator is 27 inches wide - that means that there is almost as much radiator NOT having air drawn through it, as there is getting 'cooled'.

3) AND - it sits like almost 2 inches away from the radiator! This means that ALOT of air is being pulled from AROUND the fan, rather than being drawn THROUGH the radiator. At best, this is a really poor design. Look at a clutch fan on any older GM car - there's a huge shroud - looks like a 20in tube that in some cars is over a foot deep, and encases the fan blades inside to ensure that the air is being drawn through the radiator rather than sucked in from around the sides.

So my thoughts:

1) Better cfm rated aftermarket fan - 2000 cfm fans can be had for $100 easy.

2) Aftermarket fans are usually mounted by use of heat resistant zip-ties things that poke through the radiator fins - this puts the fan right up against the radiator, ensuring that air is drawn through radiator rather than around it.

3) Shrouding - I went today to Lowes - got 14in x 10ft aluminum roof flashing roll for $11. I cut to fit, riveted through small holes I drilled in the electric fan housing, and cut to fit the space. Took me about 2 hours, cost $11, and should drastically improve the drawing of air through the radiator, and through a much greater surface area of the radiator than the 16in circle the fan covers. I didn't disconnect any hoses or need to remove the radiator - just removed the fan to trace the circle, and fitted back in gradually, snipping here and there as needed to amke it fit back in. All I used was regular good scissors - the aluminum is very thin and easy to eal with (but SHARP!).

I could care less about why GM 'designed' these cars to run hot. Hotter is NEVER better, for any reason. EVERY engine prefers cooler temps. Heat kills - period. Unless you reach a point where the temps are so low that the ECM isn't efficiently burning your fuel (ie performance is less) - you can never be too cool.

camaronewbie

OK - so I tested the $11 home-made shrouding today, and it makes ALOT of difference!

My car, sitting at an idle, would climb easily to 220 (on my guage) within 5-7 minutes. I just had it running in the driveway for 15+ minutes, and the temps never went above 170. The fan kicked in several times (I need to adjust the temp back up so it doesn't come on so early), and each time it kicked in, temps fell below 160 (again on my guage) - so it wavered between 150 and 170 through 15+ minutes of idling in the driveway - which is unbelieveable in my car!

Anyone needing to bring the temps down should grab some rolled aluminum flashing from the roofing section at Lowes/Home Depot - it really makes a huge difference! Pics: http://s287.photobucket.com/albums/l...nt=shroud2.jpg

davep_96

Hey thanks everyone for your input.

And thanks camaronewbie, I was looking at the lack of a shroud the other day and was contemplating trying to fab something up so i think i'll give your idea a try.

I do currently have the stock single fan in my car. I guess I never quite understood the importance of the cooling fan until my car started having terrible cooling issues so thats why I never replaced it with an aftermarket one. Ill have to check into that, and the fan control unit, as well.

camaronewbie

FYI - I've probably jumped the gun here a bit - everyone says a 160 stat is too low. But I've got other issues I haven't traced down yet that cause me to run hot, and so adjusting my fan controller way down and adding the 160 stat is a bandaid at the moment for me. A 180 stat would be much better I'm told, and most say to adjust the cooling fan to come on about 20-30 degrees higher that the temp the stat opens at.

asfalto

how did you attach it to the radiator?
i'm very interested!

camaronewbie

It's not - it just sits there.

The radiator has a bit of a lip on the edges - where the aluminum radiator ends and the plastic tanks are held on. I just cut the width of the pieces an extra 1/2 inch than needed, then I kinda slid the fan motor/housing with the aluminum shrouding in place, then wiggle a tad and worked the edge into this lip on both sides.

So the shrouding pieces are just attached with a couple rivets to the fan housing and that's it. No need to be real pretty either, you really have to stick your head in the bay to even see it. And for the $11, you get enough aluminum in the roll to do probably 5 of them, so no worries about cutting it wrong.

asfalto

thanks a lot!!
greetings from italy!