Electric fan Vs Viscous fan?

[Andy325i]

Sorry to stick my nose in but does anyone know of any original BMW parts to make the fan run after the ignition is turned off ?
I'm thinking of trying to put an electric water pump in as well (earlier thread)

Very interested in that idea!

What rad switch are you guys using to trigger the fan? I have an E36 325i one in there atm but it comes in too hot (92/98 degrees C) What temp should the fan be cut in at?

Andy

[BrAdZ]

go to:

https://www.burtonpower.com
then- Cooling System


Then look under electric cooling fans....... Theres Thermostat adaptors that you cut a hoze and put in,

Very good system, i had one on my capri after i ditched the viscus

[Turbo-Brown]

Never really seen the point in the fan running once the engine's off. All it's gonna do is cool the water in the rad, not the rest of the engine surely?

I could see more point to it if it were coupled to an electric water pump so the engine's cooled too, BUT, the engine's not generating any more heat and so you're only gonna cool it down quicker that it would otherwise have done by itself, and where the point in that?

[Widge]

You finished that awesome GT6 yet Turbo-Brown?

[Martinaston]

Once the engines turned off it's left to cook and it may be the reason for all the cracked head units that people keep posting.

Cheers Bradz
The top hose adapter could be worth investing in as the temp switch would work better located either in the thermostat housing or as near as possible rather than in the rad because once the engine is off the rad would cool first.

[BrAdZ]

its because someone off here (sorry cant remeber name) is working out how we can work with an electric water pump so it can run when the engines off to contiue to cool the car down instread of letting all the heat sit in the head that could be causing a decreaced lifespan for the head, as we know how all 6 pots are prone to this

Adam

[Andy325i]

Just thought! The VW golf Mk3 VR6 has a unit by the bulkhead which circulates the water after stoping.

Anyone running a turbo timer?

[Guest]

stop me if im silly, but i still use the old, set the interior heater to hot and put the fans on full, you may cook in the car (just drop the windows) but it helps, my m42 engine gets really hot in this weather....

[E30BeemerLad]

the older renault turbos used to have a fan gadget that cut in after the car had been turned off. Think it was called an anit-perculation unit and was supposed to cool the gaff down as the R5 Turbo my old man had used to suffer with terrible hot starting problems. The fuel used to evaporate in the lines

[Brianmoooore]

yeah i agree with boybimmer and with widge. a leccy fan can kick in and out as often as it wants to keep the engine at its optimum temp.

The engine thermostat controls the operating temp of the engine.
The radiator just supplies suffuciently cool water for it to do it's job.

[Brianmoooore]

Sorry to stick my nose in but does anyone know of any original BMW parts to make the fan run after the ignition is turned off ?
I'm thinking of trying to put an electric water pump in as well (earlier thread)

You don't need any extra parts to make an electric fan run on after the engine has stopped.
If you wire the fan supply from a permanent live fuse, then the fan (and auxillary pump) will run on untill the control thermostat shuts them off.
Circulation from the engine will stop when the engine thermostat shuts.

There will be considerable circulation of water from the engine to the rad (if it is being cooled with an electric fan) after the engine (and water pump ) stops, because of the thermo syphon effect. Early car engines (and central heating systems) didn't have water pumps.

[Brianmoooore]

You don't need to bastardise yours E30s by fitting Ford or Citreon parts either.
The electric fan from a E34 5series or 7 series with aircon fits into the E30 perfectly with just two small fabricated brackets. A replacement rad gets you the mounting boss for the thermostat (If your still on the original rad it's due for a change anyway), and the neccessary fuses and relay socket's are present in the fusebox.

[Wilson]

because of the thermo syphon effect. Early car engines (and central heating systems) didn't have water pumps.

Can you explain this please?

[Widge]

Water acts just like air or any other fluid. As it cools it becomes more densly packed and therefore heavier. As the cold water falls to the bottom of the rad it will pull in hot water from the top of the engine and cause some circulation. Model T fords had no water pump.

[Andy325i]

go to:

https://www.burtonpower.com
then- Cooling System


Then look under electric cooling fans....... Theres Thermostat adaptors that you cut a hoze and put in,

Very good system, i had one on my capri after i ditched the viscus

Cheers dude, seen this idea before but was looking for a thermo switch to go in the side of the rad.

Does anyone know of one to do the job? doesn't matter if it has a smaller thread, as I can get an adaptor made up.

Andy

[Brianmoooore]

Cheers dude, seen this idea before but was looking for a thermo switch to go in the side of the rad.

Does anyone know of one to do the job? doesn't matter if it has a smaller thread, as I can get an adaptor made up.

Andy

One from an E34 or a 7 series with aircon screws straight in.

[Andy325i]

and I guess it would be the right temp?
(about 80/82/85?)

[Martinaston]

Andy325i
There about Ԛ£20 from ECP for 91/99c but not sure if they do a lower setting. If your trying to get the coolent that low (80-85) will that not set the ECU to over fuel ?

Cheers Brianmoooore
I had an idea you would come up with the goods, I didn't fancy putting any French bits on the car

By the way did you notice how that electric water pump was plumbed in ?

The reason i ask is that i'm thinking of fitting one so that i draws the coolant from the rear of the head because as you (and Widge) explain the coolant circulates on it's own when the thermostat is open . But from what i've seen and can work out it only circulates around the front one or two cylinders. From the water pump back up to the thermostat and back out leaving the rear to continue to cook, especialy on a hot day when you leave the heater setting on cold and effectively shutting that hose.

From all the engines i've seen (and one of my own) the head gasket or the head itself has failed at the rear of the block and never the front.
BMW designers are aware of fluid dynamics thats why they put the throttle body in the centre of the six cylinders to even out the flow of air as much as possible to each intake. Yet when it comes to putting the coolant in it's pumped in from front to rear

So what i'm thinking is a temperature switch at the back of the head and the pump plumbed in to bypass the heater matrix and run back to the radiator.

Any thought's or any faults you can see that it may cause then pleas chime in the more input the better

[Martinaston]

To add
i'm not removing the viscouse fan so the system is to work only once the engine is off.

Also should i start another thread ?
this seems a bit cheeky under someone else's.

[john325tewerin]

I ripped a viscous fan from my Range Rover and replaced it with the electric twin fan system form Kenlowe. They are 12" push type fans and it made a very noticable difference both in noise and performance/mpg.

It's not high on my agenda but I will be putting a push type electric unit in my e30, eventually. For the undecided, you could always have an auxillary set-up ie, an additionl electric fan ala m3.

[Andy325i]

Andy325i
There about Ԛ£20 from ECP for 91/99c but not sure if they do a lower setting. If your trying to get the coolent that low (80-85) will that not set the ECU to over fuel ?

The temp doesn't run that hot mate, I already have the 2 in one switch from an E36 325i and even on 91 it goes to 3/4 up the gauge before cutting in

Andy

[6potWil6pot]

The lectric fan i had in my old car would activate 2/3s and keep the temperature there in traffic. Would only drop down to 1/2 way on the move.

Anyway isnt there only a few degrees difference in heat in the temp gauge, so there isnt much of a diff between half and 3/4?

[Martinaston]

Andy325i
if your temp guage takes some time to get moving after starting the engine then its probably reading at the higher end of the scale.
I've had a set of clocks read at 1/4 in one car and 2/3 in another,
I think it depends on the reistor in the temp sender for the guage and the condition of the wiring.
If the fan kicks in and cools it down then there's not a problem.
Unless your trying to get it to run cooler, in which case see if you can get a thermostat that opens at a lower setting.
But as i mentioned the ECU will think its still cold and over fuel the system to try and warm it up.

anyway good luck top gears on and there shooting clarkson in the face.
nice work if you can get it.

[Brianmoooore]

By the way did you notice how that electric water pump was plumbed in ?

:

The M54 electric pump draws water from the bottom of the header tank (which has two bottom connections) and feeds it into the rear of the engine water pump housing. Water comes out of the engine just below inlet port 1 at the front of the engine, and goes via a plastic pipe and a hose, towards the back of the engine, and presumably to the heater.
The second connection on the header tank has a very long hose on it, long enough to reach the rear of the engine bay, so presumably this is the other heater connection.

[Turbo-Brown]

You finished that awesome GT6 yet Turbo-Brown?

I've been a bit distracted of late by my "Turboing-Brown" project.

Think they GT6 is gonna be one of those projects that just goes on and on and oooooooon!

[Martinaston]

Cheers Brian
Sorry to be a pain but do you know if that pump will allow water to pass if it is not running ?

[Brianmoooore]

Cheers Brian
Sorry to be a pain but do you know if that pump will allow water to pass if it is not running ?

Yes, it's just a centrifugal pump like the engine pump.

[M3Compact]

Great idea, 'back up' electric water pump imo.

Electric V Viscous led me to try an 'alternator cut off switch' with an electric fan.

Bizarre theory, but effective and cheap. (Untried on my BMW so far, but has worked on other cars.)

Basically, borrowing electricity from the battery when full engine power is required, paying it back when engine revs are surplus to requirements.

We've used a spring loaded throttle cable switch from an automatic Ford granada, Ԛ£20 + a relay, and a couple of hours wiring.

No help with economy, but never, ever an engine power drain for cooling, when you've got full gas pedal on.

http://forum.bmwcarmagazine.com/topic2. ... C_ID=20038

[E30BeemerLad]

whilst were on the subject of our friend the viscous fan, what's the deal with getting the nut off? I am planning on doing cambelt next weekend and understand the nut is a bit of a cnut to get off. It's left hand thread too innit?

Do I need a special spanner?

[dazleeds]

your already half way there remebering that its a left hander thread
most imho dnt know and have loads of grief not sure on the size so a nice big adjustable works best and if ya lucky 1 good crack will free it up but if not then loosen 2 nuts from the pulley behind the coupling take 1 out and put a small ringspanner onto the bolt and then thread halfway back in then sit the spanner on the other loose bolt now you can hold everything still and get a little brute force onto the adjustable and should be off in no time mate
well worked for me last time i had to get a tight bugger off

nice to see your doing the belt at last mate must get mine sorted the way i fly round its just a matter of time before the fooker goes ping its on me list good luck mate Daz

[E30BeemerLad]

cheers mate, I think i'm driving a time bomb too and I haven't slowed down much either lately!

It defo needs doing, current one has had 55K hard miles! Was in a dilema last week, a garage I know well quoted me Ԛ£90 labour with me turning up with the parts. I was thinking Ԛ£90 or do it myself. Hope I don't have any regrets!!!!!

Dave (Cabrio327i) lives about 10 mins from me and has offered some help if I need it, which I most certainly will me thinks!

Might get the tappets adjusted and stick the tarted up cam cover I have sprayed on at the same time.

[Martinaston]

If you have an old belt and a pair of mole grips you can clamp the pully but that means removing the original belt.
I found doing it the Daz way works best.