Hello, I have installed a universal radiator fan into my wifes BMW. The BMW fan cost about $300 but I found a universal one on ebay for $33 and I put it in there and it keeps the coolant cool just the same. I let the car sit parked and running for a while to verify it would do the job and it does the job very well and I am pleased with it. I had it running on a direct 12v line temporarily to see it work, but now I want to make the install permanent which brings me to my question. The way I hooked the fan up, it was running at full speed and I want to have it run maybe a little bit slower. Would I be able to accomplish this by installing a fuse in the line and experimenting with less and less amp fuses? Or would that not affect it? Would weaker fuses give it less power or would I have to find a way to give the fan less volts? I am going to use a 12v ignition wire that only has a current when the car is running, but I dont necessarilly want the fan to run at full speed so what would be the best way to slow the electric motor down? Any ideas would be helpful. Thanks
Wow These are ALL very good and answers and explanations. Its very clear now, I dont know why I was thinkin I could just put a weaker fuse in the line and somehow my fans motor would get less power through that weaker fuse, the fuse would just blow like it is meant to do. Now it would definitely be ideal to just wire my fan to the original fans wires but there is a major reason that I cant do that. The BMW fan that I am replacing actually has its control unit built into it and the wires that go to it always have current flowing to them even when the car is off. I know my car does have a coolant temperature sensor in one of the radiator hoses and that is what they used to control their fan but I dont really want to mess with all of that. I was trying to keep my project kinda simple. Maybe I will get brave as I learn more! For now I will just wire it up to run whenever the car is on, if my fan burns out once a year, well at least I know its only $33 not $300 for BMWs fan. Thanks every1
Wow These are ALL very good and answers and explanations. Its very clear now, I dont know why I was thinkin I could just put a weaker fuse in the line and somehow my fans motor would get less power through that weaker fuse, the fuse would just blow like it is meant to do. Now it would definitely be ideal to just wire my fan to the original fans wires but there is a major reason that I cant do that. The BMW fan that I am replacing actually has its control unit built into it and the wires that go to it always have current flowing to them even when the car is off. I know my car does have a coolant temperature sensor in one of the radiator hoses and that is what they used to control their fan but I dont really want to mess with all of that. I was trying to keep my project kinda simple. Maybe I will get brave as I learn more! For now I will just wire it up to run whenever the car is on, if my fan burns out once a year, well at least I know its only $33 not $300 for BMWs fan. Thanks every1