Long story short my viscous fan clutch has been not working for a year or so. I finally get around to buying and installing my new one.
I took the old one out and was surprised at how heavy it actually was, compared to its size. Shipping weight for the new one was 3 lbs, plus fan weight, and wind drag.
Well the new one went in fine, but Im fairly certain my car is now (considerably) slower. The old/broken one spun freely, with minimal drag. The new one seems very tight and spins alot faster.
now im contemplating switching to electric fans, are there good brands to look for? pros/cons?
3+lbs of rotating mass would be good to get rid of I believe, but if there’s anybody out there smarter than me in terms of thermodynamics, wind resistance, etc, Im all ears for your argument
No you are right. Get rid of it and get an electric fan if you have a fan shroud get one that will fit inside it and fasten tight to the radiator. You may need to wire up your own relay since it did not come with one but there are kits for that.
well, since my fan has been out for so long with 0 overheats, needle crept a little past half when in traffic for a bit, I was wondering about just wiring a switch to an electric fan, so when I know Im going to be stuck in traffic, or under extreme heat conditions, I can just flick it on. Then keep it off under cruising conditions and restoring powaR
Get an electric fan with the appropriate thermal switch wired to a relay.
Pros:
Less parasitic drag on the motor due to air and weight resistence, also less rotating mass on the WP equals longer WP life.
Cons:
Get a fan wired to a therlam switch and there wont be any.
Seriously though dont go the manual route. Do it right. Specuially if its for the Bimmer in your sig. You dont want to put too much heat in a straight 6
manual = oops i forgot = blown HG and other problems.
even if the old one was crap, it was probably still moving a little air when sitting in traffic. elec fan that is off is moving no air.
get a temperature based controller (or make one… LM324 op amp comparator, voltage regulator, simple voltage division circuit and a temperature sensor mounted in the t-stat box on the engine side, a MPS2222 transistor, a few resistors and a 12v automotive relay) and hook it to the fan and enjoy automation.
idk, i run a fan clutch and i still made over 550whp.
Also the reason you never overheated is probably because the electric fan for the ac condensor automaticalt turns on after a certain temp. there should be a low speed and a high speed if its anything like an e36.
I run an electric fan on a manual switch. I have no “oops I forgot” situations. It has become pretty much second nature to flip the switch on/off and I don’t think I’ve ever forgotten. Worst case scenario you just flip it on right when you turn the car on and then you won’t have to worry about remembering to turn it on later once you’re already driving.
this is discussed all over in the E36 forums on bimmerforums.com they sell specific kits for replacing the clutch fan. It comes with water wetter, a lower temp thermostat, a nut to cover the and of the fan threads, and a variety of different fans. But definitely get the relay.
I don’t understand why you would want it on a manual switch. The cons are that you could forget to turn it on, you’d have to install a switch in the cabin somewhere that probably won’t look that great, extra wiring. Are there any pro’s to it at all? Is a temp switch expensive or something?
Interesting thread. I just pulled an electric fan out of a Taurus to use. My fan is hooked directly up to the water pump pulley - no clutch. There’s no shroud, and the blades are sharp sheetmetal. :eekdance:
Let me know how your search goes, I’d like to do the retrofit this winter :tup:
I was in the exact same situation with my Supra. I wired in an electric fan from a Ford Taurus. Many people go with these fans because they flow tons of air and can be had cheap at any local j/y. I wired it in on a manual switch because I pay attention to my gauges. But in the one year that I have had it on the switch I have only turned it on maybe 3 times.
