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Electric fan options

2K views 15 replies 9 participants last post by  Michael B 2007 550i 
#1 ·
Yes, it's another electric fan post.
Why am I asking about an electric fan? Because my new radiator just ate another new fan. In November I hit a deer while driving home from work, there;s a thread on it somewhere I think. The deer smashed the hood into the radiator shroud, killing the shroud and the fan. I've replaced the hood, nosepiece, radiator, shroud, and cooling fan. The radiator wasn't leaking, but I went ahead and replaced it with an aluminum ebay unit. When the deer hit it also pushed the upper radiator support back, which placed the radiator closer to the fan. The fan was lightly hitting the retainers for the top bleeder hose even after adjusting the upper radiator support as far as i could (short of using a very large hammer). I replaced the engine mounts, and that seemed to give me enough clearance, but a few days later while a few miles from home the fan caught the bleeder hose brackets and ripped two blades off and dented up the new radiator.

The point of that story is that I have tried to fix the car using the correct parts, but it's not working. To start from scratch and fix it right, unbending that which is bent, would likely cost more than the car is worth. As I am short on time and funds (due to having bought a house and not yet having sold the old one) I think the best option is to abandon the stock setup and use an electric fan. I do not intend to use the auxiliary fan for this purpose, as it was not designed to handle the entire cooling load and it's nearly twenty years old.

What I need is suggestions on what fan would work well and fit, whether to integrate the fan into the stock shroud or obtain a different type shroud, what thermostat switch to use, etc. Basically, if someone has done it, I'd like to know how they did it. Keep in mind, the radiator and thermostat are new, and I'm running a Stewart water pump with less than 3000 miles on it. I'd like to keep the project under $200, but it will not be a hack job.

If you have suggestions on how I could feasibly retain the stock setup I will hear them, but as I said my funds are limited at this time and I can't afford to buy a new shroud and set of fan blades every 3 months.
 
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#4 ·
Thanks for the replies. I had seen that kit and was considering it. Is it meant to replace the front auxiliary fan or to be used with it? I wonder if it could somehow be integrated into the stock shroud for more efficiency? I have to keep the shroud anyway because of the de-aeration tank.
 
#6 ·
To start from scratch and fix it right, unbending that which is bent, would likely cost more than the car is worth.
Unless your car is only wroth $200, no it won't. You can get a brand new radiator support for only $220. If that is too much, you can get a used one even cheaper from some parting out a car.
 
#8 ·
If you have suggestions on how I could feasibly retain the stock setup I will hear them, but as I said my funds are limited at this time and I can't afford to buy a new shroud and set of fan blades every 3 months.
Since the front is already banged up and the radiator support is pushed in, get a come-along, some strong rope and pull it back out a bit. Park the car facing a stout tree, connect the come-along to the tree and the rope to your radiator support. crank the come-along very slowly until you've pulled the radiator support out the desired amount.
 
#9 ·
Alan777 It replaced the stock mechanical fan that attaches to the water pump. It can be used in conjunction with the stock shroud. That's how mine is set up.
I meant for the wiring side, does it leave the auxiliary fan functional on high and low settings or does it move all or part of that to the new fan? Sorry, I should have been more specific.

Unless your car is only wroth $200, no it won't. You can get a brand new radiator support for only $220. If that is too much, you can get a used one even cheaper from some parting out a car.
So $220 for the support (and I'm not sure that it's the only thing that's bent so that may no completely fix the problem), plus $52 for a new shroud and $30 for the cheap set of stock fan blades. And after that $302 there's no guarantee that I wouldn't lose another fan in a short time. For a car with 300,000 miles on the clock I'm not sure that gamble is worth taking. At least with the electric fan my new radiator is safe and the car is drivable for half the cost. As for trying to bend the support back with a rope, there's the possibility of also bending other things that I don't want bent, or breaking more parts by trying to bend them. I'm only trying to get another year or so out of this car before I replace it.
 
#10 ·
^Pick up a used radiator support and fan shroud for around 100 bucks off a parts car and a new set of fan blades. Then fix your car the right way and save yourself $40. It is a win-win.
 
#12 ·
^Pick up a used radiator support and fan shroud for around 100 bucks off a parts car and a new set of fan blades. Then fix your car the right way and save yourself $40. It is a win-win.
That theoretical solution requires that I find a parts car with these items intact and undamaged. It also requires that I invest time to look for said items.
Last year a truck came into our shop that had been in service for only two months, it was an electrical utility truck used to install wooden poles for power lines. When they took it off-road the fan caught on a rubber boot attached to the shroud and tore the fan blades off and damaged the coolant hoses. The parts were replaced, and two weeks later it was back with the same parts broken. We ended up fixing the same problem three times within two months. The third time the engineer we were dealing with (as it was a warranty repair) told us to leave the rubber boot off, and since then the truck has been trouble free and had no cooling issues from the missing part.
I normally prefer to make repairs to factory specs with factory quality (or better, depending on which factory we're talking about), but in this case I simply don't think it's the best answer. Enough people have had their fans explode in these cars that I would definitely call it a flawed design, and though you can under normal circumstances prevent this failure by replacing the blades regularly the fact is that most other cars never need their fan blades replaced. To replace a high failure item with another high failure item when a comparable item is available which probably won't fail and if it does will at least not take out other parts when it fails just seems pointless at best. To me the "right" fix is the one that will go the longest without failure and is the least likely to leave me stranded on the side of the road, and at this point I have no confidence that the stock setup can do that.
 
#13 ·
Clearly you came in here looking for electric fan advice because you are fighting anyone who is saying otherwise. I happen to agree with you're whole "F**k that mechanical fan" mindset and run electric fan setups.

I ran this fan and shroud with my ebay aluminum radiator for about 18k miles on two different E36's. AC on in 90 degree heat in a traffic jam and my temp never rose about 195 in the thermostat housing. I wired the fan on the first car to a switch in the console which I found to be tedious, so on my second E36 I wired it to turn on via a relay when the front aux fan turned on "high", aka 88 degrees C due to my lower temp radiator switch. Cheap, crazy effective, and pretty easy.
 
#14 ·
I wasn't trying to fight anyone, I simply gave my reasons as clearly as I could. I did end up getting the Spal fan kit and installed it three weeks ago. Installation was very easy and very clean, and so far I have been completely happy with it.
 
#15 ·
Yes, it's another electric fan post.
Why am I asking about an electric fan? Because my new radiator just ate another new fan. In November I hit a deer while driving home from work, there;s a thread on it somewhere I think. The deer smashed the hood into the radiator shroud, killing the shroud and the fan. I've replaced the hood, nosepiece, radiator, shroud, and cooling fan. The radiator wasn't leaking, but I went ahead and replaced it with an aluminum ebay unit. When the deer hit it also pushed the upper radiator support back, which placed the radiator closer to the fan. The fan was lightly hitting the retainers for the top bleeder hose even after adjusting the upper radiator support as far as i could (short of using a very large hammer). I replaced the engine mounts, and that seemed to give me enough clearance, but a few days later while a few miles from home the fan caught the bleeder hose brackets and ripped two blades off and dented up the new radiator.

The point of that story is that I have tried to fix the car using the correct parts, but it's not working. To start from scratch and fix it right, unbending that which is bent, would likely cost more than the car is worth. As I am short on time and funds (due to having bought a house and not yet having sold the old one) I think the best option is to abandon the stock setup and use an electric fan. I do not intend to use the auxiliary fan for this purpose, as it was not designed to handle the entire cooling load and it's nearly twenty years old.

What I need is suggestions on what fan would work well and fit, whether to integrate the fan into the stock shroud or obtain a different type shroud, what thermostat switch to use, etc. Basically, if someone has done it, I'd like to know how they did it. Keep in mind, the radiator and thermostat are new, and I'm running a Stewart water pump with less than 3000 miles on it. I'd like to keep the project under $200, but it will not be a hack job.

If you have suggestions on how I could feasibly retain the stock setup I will hear them, but as I said my funds are limited at this time and I can't afford to buy a new shroud and set of fan blades every 3 months.
 
#16 ·
I have similar issue with a fan not working on a 550i BMW therefore causing the car to overheat when I am just idling which I've learned not to park and sit with the car just running. It was hard enough to just figure out how to read the temperature of the car from the dashboard by just pushing the odometer button in several different sequences. The point I am at is it's not the fan that is going to cost me it is the housing for the fan because two oil cooling lines run through it and anything they sell on eBay supposedly is not deep enough or the fan does not accommodate the new housing for with the oil cooling brackets.at first I was limited on space so I was going to go ahead and divorce the fan and housing that it is in and just by a small aftermarket two-wire fan off of eBay that connects simply with a small housing and zip ties to get me by which would still work. The only difference is that the existing fan has three wires positive negative and I guess one is for the sensor which I have gotten rid of and have had no issues on the readout about anything to do with the sensor my suggestion would be to buy and aftermarket fan and housing and measure how much space you have whether it be two three four inches. Or feel free to call me I may be able to guide you in the right direction along the lines of just replacing the fan based on the bolt configuration and what other fans would fit in the housing you have the name is Mike 734-322-7470
 
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