Swap to electrical fan for radiator?

J

johanaxelson

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Any thoughts on doing that?

The reason I ask is my regular fan for some reason got caught in the metal stripe on the radiator and lost two blades.

I could now replace that one or use the electrical fan I already have in front of the radiator.
It is there for the A/C cooler that is placed in front of the regular one.

In theory that should be enough but....

Thanks,

Johan
 
Elec fan

Sure, as long as it's not the original a/c fan which helps but doesn't blow but about 200 cfm. I've seen 320i fans, aftermarket, etc. Suggest you alter to two speed with two step sender and resistor for those hot stop and go days.

Alternatively, and perhaps faster..... loosen the motor and trans enough to move/ shift rearwards. And one more thought, you can alter the rubber radiator isolators or mouunts by cutting the vertical part and shift the radiator forward a bit.

Not unheard of in a swap or major rebuild.
 
Thanks, I actually had moved the radiator since it was close. But....

It is not so easy to move the engine and trans is it? The mounts looked pretty fixed to me.

I also do not think it is the original fan. Looks a little bigger. I will try to measure it for comparison. Good thinking with the two step :)

/Johan
 
It is a pretty common mod for the later cars (E34, E36, etc) since the fans like to randomly disintegrate past a certain age, taking lots of expensive parts with them.

I've seen it implemented as a physical switch in the cabin, which requires a bit of personal monitoring, and as a relay-activated unit running off its own temperature sensor. On the plus side of things, you don't have to worry about replacing a bad fan clutch again, and it will work regardless of engine speed. On the downside, it sucks quite a bit of electricity. In the more modern cars this isn't a big deal, as the alternators are vastly more powerful. The stock E9 alternator is pretty weak by modern standards, so I'd be a little wary about just slapping an electric fan on the system due to excessive draw. Plus, the wiring would either need to be new or seriously beefed up from the stock AC puller fan, which, as 61porsche noted, is pretty weak.
 
I think my alternator is upgraded. Do you know how many watts the original one produced?
And the fan is already there and working for the A/C.

Would probably not do it as a physical switch, maybe as a backup, but rather use something like this instead :

http://www.biltema.se/sv/Bil---MC/B...nda/Adapter-for-termostatgivare-for-kylflakt/

In Swedish but I think you get the idea. Am open for other ideas though. I can plugs in it for different temperatures. Lower in summer etc.

And yes, there are several upsides. Less engine noise would be one as well even if it is not a major factor.

/Johan
 
Aux fan amps

The original fan had a 25 0r 30 amp fuse; enough to run a modern fan since the fans got much more efficient. Unless you're running a big draw with a stereo and amps; I wouldn't worry much. The two temp switch goes in the radiator where the drain plug is. The resistor goes next to the fan ala a big coupe.( e24)

Past E9 era, the fans all pushed 400 cfm from my research. There are fan thermostats that have a sender ( bulb type) that just stick in between the fins of the radiator and fairly cheap- $30 here. I would recommend a bypass manual switch just in case.

SF Don had a good picture of a recent install he did or the 2002 board guys have a great wiring diagram if you need it.

The motor trans is somewhat adjustable. Pushing rearward might gain 3/8 to 1/2" if that's enough.
 
I used an AC Delco CS130 105A alternator in my 72 Bav, and it was almost a bolt-in swap. I had to change a little wiring, but it works like a trained pig. I also deleted my mechanical fan in favor of an electric fan from a 90's 525, controlled by a dual thermo switch from the same car and a Volvo 2-speed fan relay. The electric fan has only come on twice in the last 6 months, both times I had the car idling in the driveway for a long time.
 
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