advice needed on fitting electric fans only

Post Sat Apr 16, 2005 7:02 am

Well guys summer is upon me and that means 50degree heat and the cab gets stored! now you lot in uk are the lucky ones tops down and windows open etc...

But it doesn't have to be this way for me, normally my cab does not like the heat and runs a little hot, tried all normal things (flushing,clutch,different coolant etc) but no luck. So i have found in a scrappies a 944 porka with a set of double fans. This would mean removing the viscous clutch and fan, and replacing with the two elecrtic fans. So does anyone have any comments on the implications of doing this, and any advice or pictures (will6potwill!!)

ta

mrlee

Post Sat Apr 16, 2005 9:45 am

I can't help with the physical installation of the fans but have some info for the electrical side of things.

You need a temp sensor of some sort a relay to switch the fans from the sensor and some wire of the right gauge.

I've seen temp switches that solder on, it may also be possible to source a rad fan switch from another type of vehicle (Maybe Porsche 944) and plumb this into the E30's cooling system.

Locations for the switch/sensor should be the top of the rad or between the rad and the thermostat housing. I would back this up with a manual over-ride switch somewhere in the car.

The rest of the wiring should be straight forward.

A fused permanent live from the battery to the relay and to the temp sensor/switch, a ground lead to the relay and fan motors and a switched live to the over ride switch.

This should give your car the ability to cool itself automatically with the ignition either off or on, ideal as the engine will heat soak when switched off due to no coolant flowing round the engine.

The manual over-ride switch, just in case you need it, switched with the ignition so you can't leave the cooling fans running endlessly leaving you with a flat battery.

HTH

Post Sat Apr 16, 2005 11:05 am

IIRC, from a previous thread, you have aircon on your car, so you already have an electric fan in front of the rad. Can't you just wire a manual overide switch to that if necessary? Or are we talking about a different E30?

Post Sat Apr 16, 2005 3:37 pm

I fitted an electric fan to the front of my 320i rad recently and there is very little room in there, the plastic cowling that directs air from the grille to the rad needed to be cut to allow the single fan to fit.

I seriously doubt that 2 fans would physically fit.

I have Ian332isport's wiring description if you'd like it ? drop me a PM with your email addy and I'll send it.

I was lucky and have a replacement radiator with a 14mm threaded boss for a temp switch, not sure how you'd go about mounting one if you have an original rad.

Cheers,

Iain T

Post Sat Apr 16, 2005 6:21 pm

I wired in a 16" fan infront of the Radiator when I did the m30 swap. I made my own wiring harness ussing 2 relays, a brand new aux fan resistor and the Temp switch in the radiator for the AC Fan. Basically when the car is on the fan runs on a low speed threw the resistorm then once the switch in the radiator hits a certain temp, the fan kicks in on full power(enough to shake the car

)

Post Sun Apr 17, 2005 11:03 am

cheers all, v help full and was the route i was going down anyway. the plan is to fit the porsche double fan AND the electric fan. Yes brian i have A/C and yes i have a manual override but that fan really only helps to cool the radiator matrix for the A/C, leaving my engine slowly rising in temp when sat at lights, i am aslo going to put a timing device in there to keep the fans running for a couple of minutes after ingition is off. As you all put there is no space in front of the rad so between the rad and engine is the only place, wired through a heat sink/switch and a manual override. My main concern wasn't so much the electrical side of things but the issue of completely removing the viscous clutch and fan currently in there!!. Any comments on that??

would like ians wiring diagram so PM sent (cheers templ8)

Post Sun Apr 17, 2005 4:14 pm

mrLEE30 wrote:My main concern wasn't so much the electrical side of things but the issue of completely removing the viscous clutch and fan currently in there!!. Any comments on that??

I dont think there are any problems with removing the viscous fan. Its meant to free up some extra bhp, but I dont know how true that is.
Ian332i has no viscous fan on his S50 conversion and neither have I, and Im sure there are some people on here who have removed them from M20s as well.

Post Sun Apr 17, 2005 5:32 pm

I have a M50 conversion on one of my cars as well. The viscous fan is not fitted because of space issues, and I have fitted an aircon fan from a seven series (late 80s type) in front of the rad.
This is just about the maximum size single fan you can squeeze in there, and is the same as fitted to the E34 five series. Don't know if aircion E30s use the same or not.
When on full speed the fan shifts a lot of air - seems like nearly enough to move the car along. I would have thought this was enough to cool the car, but of course I've never tried it in 50 degree ambient.
Maybe some of the internal waterways in the rad are scaled up, and it's not working at full efficiency. New rad might be a good idea

Post Mon Apr 18, 2005 7:34 am

cheers all,

done the flush thing and all good, car only 90K km and all E30 here (i have two) do the same, guess not designed for such intense heat, 50 degree and 80-90% humidity means that the water in the air is almost 30-35 degree so cooling is a problem (both for the car and me!) not too bad while moving but at any stop the guage creeps up slowly but surely!! Seen a porsche with double fans (each about 10inch) which at first glance will fit where the viscous fan is, them plan to make a fibreglass or plastic shroud to seal it in a bit to get max air flow through rad (and not into airbox!! although performance at that temp is not worth discussing!) maybe the lack of viscous fan wil make up for the performance loss due to air temp and density!

thanks all

Post Mon Apr 18, 2005 9:37 am

I can't vouch for this type of stuff but it's worth a look.

http://www.racerpartswholesale.com/redline3.htm

http://e30m3performance.com/myths/more_ ... wetter.htm

http://www.cuttingedgecasemods.com/h2o/watrwetr.htm

HTH

Post Mon Apr 18, 2005 11:46 am

Hmmm certainly worth a try!! if i can get it, bit concerend when it says not to overwet your water!!!!

FYI i have found (after much experimentation) that the best hot weather coolant is Mitsubuishi's own brand. It comes in a litre tin and opens like a can of beans! and is mixed with de-ionised water (to prevent corrosion) and whilst not cheap it is the dogs danglies, better than the rest by a distance.

thanks alll for your help i will let the zone know if i am successful!!

mrlee

Post Mon Apr 18, 2005 1:09 pm

Templ8e30 wrote:
I was lucky and have a replacement radiator with a 14mm threaded boss for a temp switch, not sure how you'd go about mounting one if you have an original rad.

What temp switch are you using mate, and how hot does it get before kicking in?

Post Mon Apr 18, 2005 8:09 pm

How about a bigger radiator? It looks possible to fit the E34 rad in my M50 E30 if I needed to.