Show me your electric fan conversion

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crazy4offroad

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Went to the junk yard this morning, they actually let me walk around with my tape measure. Sure enough they did have several Windstars, and I even found one with the radiator & grill removed so the fan assembly was easy pickin's. All I needed was my knife, used as wire cutters by closing the blade on the heavy gauge wires. We hooked them up to a battery they had on hand just to verify they worked, and I was good to go at only $40.

When I got home I set it in place on the truck and noticed the driver side mounts were in a good location to be attached to the radiator support using long bolts and body clip fasteners...
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I'm thinking of redoing these, using a piece of pipe to limit how tight the bolts can be tightened. The lockwashers are pretty much doing nothing and the plastic arms just bend.

Next I fabbed a simple clip from heavy gauge sheet metal to hook into the plastic and bolt to the upper radiator bracket...
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Clip bolted in place...
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Soldered, heat shrink tubed and routed the wires...
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Nice view of all the room in there now...
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I got the relay/control box all hooked up except for extending the wires for the sensor probe. I cant understand why they only put about 10" of wire for that. Also still need to mount it under the dash and tuck away the wiring. Anyway, with everything else hooked up, I twisted the sensor wires together and they kicked on just fine. They seem to move a good bit of air but honestly I think the Camry fans move more, it may have to do with the fan blade design. One very nice thing is you cant really hear them run, probably because of the fan blade design.

On the passenger side I'm going to cut off the mount arms since they seem to be right in the way of the trans cooler connections. Also there is a hole made in the plastic shroud, probably to clear something on the van, that I'm going to pop rivet some sheet metal over so it will have better draw across the radiator. I ran the truck at idle, let the temp gauge get up past the 1/2 mark then turned the fans on. They were able to cool the truck down to just under 1/2 but no further. I'll report back after I get the sensor probe hooked up and give it a road/trail test, hopefully this weekend. I think I'm also going to hook up a mechanical aftermarket temp gauge I have just so I can verify exactly what temp the truck is running at.
 

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89Suburban

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Nice job man! :grd:
 

bucket

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Mine has those side mounts simply cut off and it's bolted along the top, to the radiator top cover. Then some tabs hold it at the bottom.

Do the fans cool the motor down and then turn off, or do they just keep running?
 

crazy4offroad

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I have the temp sensor mounted in the radiator but cut the wires so I could lengthen them which I havent done yet. So I just stripped/twisted together the sensor wires at the control box and they stay running. I have the yellow wire hooked to ignition so they will turn off with the key. I will however wire in a switch to the sensor wires so I can override the sensor if needed and have them stay on continuous.
 

austinado16

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Nice work.

You might want to buy an infrared temp gun. Ebay or Harbor Frieght, or probably Amazon. Fantastic tool, so buy a good one. You'll wind up taking it with you everywhere and shooting the temps of all sorts of components....like trans pan, aux trans cooler, engine oil cooler, radiator top and bottom hoses, tire tread, diff housings and on and on. You can also use it to diagnose cylinders that either aren't firing (exhaust runner will be cooler than the rest) or are running too lean (exhaust runner will be hotter than the rest).
 
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crazy4offroad

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I have one, but would rather have a temp gauge with increments of actual degrees rather than a temp gauge that looks like a fuel gauge, just marks. The ole truck was starting to run a little warmer than 200 before I swapped the gauges around, and the factory gauge it was leaning on the 3/4 mark so I swapped in the 180 degree thermostat which shaved it back down to just a hair above 1/2. So that got me wondering what the reading actually is, hopefully below 200.
 

crazy4offroad

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Just got through hooking up the sensor and toggle switch and testing it out. Not real happy with the control box. I fiddled with it for a while till I got it to kick on at the 1/2 mark but it runs the fans for 15 seconds and off for only 10 seconds, even on a cool rainy day like today. There are other possibilities I have to look into though, I think my factory gauge is a 1973 model and the temp sensor is a 1980, might be a voltage difference there and the truck is actually running a lot cooler than I think it is. Also this engine has been rode hard, it could have a burnt valve and just runs hotter than it used to. Anyway after I get my running done today, this evening I'm going to look into swapping out the factory temp gauge, and get a Sunpro temp gauge installed as well. THEN if it is running cooler like I think it is I can adjust accordingly. It's scary to see the factory temp gauge up in the neighborhood of the 3/4 mark which is where it was with the factory fan and 195* thermostat.
 

austinado16

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Was at the local yard today to see if they had any Mark 8's. They did, but the radiator and fan were long gone. However, that did have a 2001 Llincoln Town Car and it looks very promising. Huge fan like the Mark 8, but the shroud looks more like our small block shrouds. Looked very promising.
 

Busaman

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Has anybody mounted an electric fan that can still use the stock shroud? Also, what circuit is the best to tap into?
 

rich weyand

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Just got through hooking up the sensor and toggle switch and testing it out. Not real happy with the control box. I fiddled with it for a while till I got it to kick on at the 1/2 mark but it runs the fans for 15 seconds and off for only 10 seconds, even on a cool rainy day like today. There are other possibilities I have to look into though, I think my factory gauge is a 1973 model and the temp sensor is a 1980, might be a voltage difference there and the truck is actually running a lot cooler than I think it is. Also this engine has been rode hard, it could have a burnt valve and just runs hotter than it used to. Anyway after I get my running done today, this evening I'm going to look into swapping out the factory temp gauge, and get a Sunpro temp gauge installed as well. THEN if it is running cooler like I think it is I can adjust accordingly. It's scary to see the factory temp gauge up in the neighborhood of the 3/4 mark which is where it was with the factory fan and 195* thermostat.

The 1973-1978 used the GM #513321 sender, which hasn't been made in 20 years. You can find NOS on ebay for a couple hundred bucks, but Autowire makes a reproduction unit that has the correct resistance curve. Aftermarket cross-reference parts, and even the GM cross-reference parts, do not have the correct resistance curve. Autowire even has the right connector.
http://www.americanautowire.com/shop/temperature-sending-unit-5028
http://www.americanautowire.com/shop/connector-housing-temperature-sender-con

1979 and newer trucks used one of two senders with the same resistance curve but different size mounting holes. The #8993106 has 1/2" NPT threads while the #8993146 has 3/8" NPT threads. Those are easier to find.
 

rich weyand

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Has anybody mounted an electric fan that can still use the stock shroud? Also, what circuit is the best to tap into?

Fan relays have to connect directly to the battery due to the current draw. For the control, you can hook to ignition if you want the fan to run only when the ignition is on, or you can hook to battery if you want the fan to be able to continue to run after you turn the ignition off. I hooked mine to the battery, which saved me running a wire from the cab, and also lets the fan run as long as it is needed.

I don't tow or plow or sit in stop and go traffic all the time, so I used a pusher in front of the radiator. No shroud, so I get ram air through the whole radiator whenever I am moving, which seems to work for me. The fan hardly ever turns on.

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That's a Flexalite Syclone 398. I used the Flexalite 31149 controller. The fan is 16", 2500 cfm.
 

Busaman

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thanks for the response
 

fussfeld

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Concerning salvage yard fans:

Are the GM electric fans reversible? In other words, can they push or pull depending on which way you wired them?

i''ve just finished installing and wiring my fan (out of a 2004 cavalier). But the fan doesn't work. The toggle switch lights up (i'm only using a manual switch) and i think all the wiring is good. i'm ASSuming black off the fan is ground? The other wire is green.
 

foamypirate

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Concerning salvage yard fans:

Are the GM electric fans reversible? In other words, can they push or pull depending on which way you wired them?

i''ve just finished installing and wiring my fan (out of a 2004 cavalier). But the fan doesn't work. The toggle switch lights up (i'm only using a manual switch) and i think all the wiring is good. i'm ASSuming black off the fan is ground? The other wire is green.

The fans I grabbed from a 97' 3.8L Camaro were reversible, not sure on the Cavalier fan.

While we are at it, here is my electric fan conversion (and a slightly more involved engine conversion :D ):

Two e-fans from a 97' 3.8L or 5.7L Camaro, 454 HD cooling Squarebody specific radiator (Spectra Premium CU730), and a Tejas Steelworks aluminum fan shroud.
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fussfeld

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How to test an electric fan?

i can hear the relay click when i hook/unhook the battery. i have power to the relay on constant 12V. The toggle switch which is wired to key on 12V does light up when the key is on. The ground from the fan is to the frame and is pretty solid.

So i think the wiring is good.
 

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