Author Topic: electric fan (Read 6136 times)

4banger · « **on:** March 01, 2010, 02:44:11 PM »

where can i pull 12v in the engine bay to run a fan that will only be hot with the ignition on?

tjts1 · « **Reply #1 on:** March 01, 2010, 05:17:57 PM »

The existing efan power source.

4banger · « **Reply #2 on:** March 01, 2010, 05:18:48 PM »

will that switch the fan on when the ignition is on?

1991 E30 M42 · « **Reply #3 on:** March 01, 2010, 05:52:36 PM »

I put a relay under the hood that gets power from the main main power under the hood and gets signal from a controller (I used a voltage activated switch as a fan controller), but you could give it signal from the accessory fuse box. or any ignition hot.

deekay · « **Reply #4 on:** March 02, 2010, 11:28:57 PM »

i had already removed the AC condensor, so my friend and i put an e36/volvo electric fan in place of that and wired it to the same circuit that the stock aux fan uses (we wound up needing a bigger fuse, but it works).

now it comes on when the temp gauge hits the 3/4 mark, or when you push the AC button with the snowflake, and the next time i need to do belts it will be a ridiculously easy job. i'm happy with it this way.

1991 E30 M42 · « **Reply #5 on:** March 02, 2010, 11:58:38 PM »

http://www.jaycar.com/productView.asp?ID=KC5377

tjts1 · « **Reply #6 on:** March 03, 2010, 12:18:50 AM »

Quote from: 4banger;88647

will that switch the fan on when the ignition is on?

No, it will switch on when the temp sensor is hot enough or the AC is on, just like the stock efan.

Quote from: deekay;88748

now it comes on when the temp gauge hits the 3/4 mark, or when you push the AC button with the snowflake, and the next time i need to do belts it will be a ridiculously easy job. i'm happy with it this way.

You can replace your existing fan switch with a colder E36 switch to have it come on when the temp gauge is at 1/2.

4banger · « **Reply #7 on:** March 03, 2010, 12:29:13 AM »

none of the wiring is there for the stock electric fan. my is fan is wired that way and it dosnt do the job here in the nor'east when our summers are over 100 degrees with 100% humidity. id prefer to wire mine to a switch in the dash. myabe a open/closed switch like a rear defog or hazzard switch.

Ryann · « **Reply #8 on:** March 03, 2010, 12:53:53 AM »

The beauty of the M42 e30 to me is how well it's put together. I hate clutch fans, too. But I have a rough time justifying the install of a Volvo electric fan/auto parts store special, and I've owned 242 GT's, 240 Turbos, SAAB 900 Turbos, and A1 VW GTI's (which came equipped with electric fans). None of which came remotely close to the sophistication of our cars. For most folks, I think that repairing what's there is the most direct course to an enjoyable driving experience. -conservative nerdoid.

4banger · « **Reply #9 on:** March 03, 2010, 01:33:21 AM »

clutch fans are such a pain in the nuts anytime you have to do any work to the front of the motor or radiator.

deekay · « **Reply #10 on:** March 03, 2010, 01:34:43 AM »

Quote from: tjts1;88751

You can replace your existing fan switch with a colder E36 switch to have it come on when the temp gauge is at 1/2.

someone else mentioned that to me also, but i put on a modified valance with the bar across the middle hole deleted at the same time and kinda "repurposed" the shroud, it's tucked up under the bottom edge of that center hole:

i'm probably explaining this poorly, so pic:

after this the car started stabilizing operating temperature at about 3/8ths... i guess it's getting a lot more ambient air now. it's only climbed over halfway once when i was stuck in traffic on the 405 and the e36 fan pushes so much air it cooled back down immediately when i pushed the button.

i may be being lazy because i don't want to take the front end apart again, but i think it'll be fine.

tjts1 · « **Reply #11 on:** March 03, 2010, 02:36:15 AM »

The problem is (as you mentioned) when sitting in traffic. Combine that with some summer temps and allowing your engine temp to constantly spike up to 3/4 will do a number on your head gasket. Better safe than sorry.
http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait=N&make=POR&model=BE36§ion=WATrad&page=1&bookmark=2&part_number=61-31-8-361-787-M85
61-31-8-361-787-M85

If you are using the existing aux fan circuit, you should also be able to hit the AC button to switch on radiator fan.
good luck
Justin

deekay · « **Reply #12 on:** March 03, 2010, 07:41:27 PM »

Quote from: tjts1;88757

If you are using the existing aux fan circuit, you should also be able to hit the AC button to switch on radiator fan.
good luck
Justin

i thought i mentioned that above, but i may have forgotten. that is how i turn it on now when i see it at/above halfway, it's never actually hit the 3/4 mark.

but the switch goes in the radiator huh? i can probably handle that... just didn't feel like taking the bumper/valance off again just to do a switch when i usually am keeping a close eye on the gauges anyway.

i moved to a new apartment walking distance from school so i am driving very infrequently now anyway, but that part will go in my next round of mods whenever the GI bill finally starts paying out. i don't like bringing my car into the shop unless i've got a worthwhile round of stuff for him to do so i have a new gauge pack ready to go in, still need engine and tranny mounts and a new battery.

tjts1 · « **Reply #13 on:** March 03, 2010, 08:28:57 PM »

Its in the side of the radiator near the passenger side headlight. Its a 2 minute job. Don't even have to drain the radiator.

EDIT: I think I'm going to try to move my fan to the front of the radiator as well. Just have to figure out how to reverse the flow of air through the radiator.

Ryann · « **Reply #14 on:** March 03, 2010, 08:38:42 PM »

Changing DC motor rotation is as simple as flip flopping the two leads.