FMZIP's Fat Daddio Electric Fan DIY

[Redshift]

While the baking pan is ingenious idea and probably less work, I like what I did and it's holding up well. Another advantage over pan is that aluminum sheet like mine is bolted to corners of shroud which makes it less likely to flex.
http://www.bimmerforums.com/forum/sh...most-completed

This is the best thing I've seen yet. This is what I will attempt I think.

[philly98540]

I still like the cake pan personally. Any know if the 20" cake pan fits the HO8 shroud? I thought it measured 19 and some change, but I can't remember.

[NLu]

I just measured mine... 19-7/8" inner diameter

[BMW540san]

This is the best thing I've seen yet. This is what I will attempt I think.

Let me know if you want to know the thickness of the aluminum plate. I was able to get mine through a friend but if you have to buy, Amazon sells them for decent price.

[geargrinder]

Let me know if you want to know the thickness of the aluminum plate. I was able to get mine through a friend but if you have to buy, Amazon sells them for decent price.

I'm interested. So your friend cut it from your cardboard template then? What did he cut it with - waterjet? I could fab something w/ my nibbler fairly clean but it wouldn't be as tasty clean as yours.

[Redshift]

Yeah, what thickness did you use? I want heavy enough gauge to be stable but not so thick that it's heavy and weighs on the plastic shroud.

I think I can use a bandsaw at my buddy's shop to cut this after I make a template but will have to remove the shroud to do so of course. Which means car down again. Maybe it's time to buy another shroud.

[geargrinder]

Which means car down again. Maybe it's time to buy another shroud.

I have been pounding the yards looking for a cheap shroud for this purpose... for whatever reason they are all missing or smashed up by idiots who are just trying to take one random part of therefore destroy 10 other things in the process.

[BMW540san]

Yeah, what thickness did you use? I want heavy enough gauge to be stable but not so thick that it's heavy and weighs on the plastic shroud.

I think I can use a bandsaw at my buddy's shop to cut this after I make a template but will have to remove the shroud to do so of course. Which means car down again. Maybe it's time to buy another shroud.

I've used 0.08 or 2 mm thickness. I forgot what grade but it was better grade than some cheap stuff out the there. I have reused shroud on 540 but bought new one on 528. I'd recommend getting new one as old one is already stressed by years of heat and it may crack since it's not designed to carry extra weight and vibration. Also, if I ever sell the car I can keep my Spal setup if new owner prefers stock clutch fan.

[NLu]

I still like the cake pan personally. Any know if the 20" cake pan fits the HO8 shroud? I thought it measured 19 and some change, but I can't remember.

I read through the reviews on the 20" cake pan on Amazon. It is actually 20.5" outside diameter.
V8 shroud is 19.8" inside diameter. I don't think it'll fit

[Redshift]

I've changed my mind. I'm going to look for some beefy 3/4" aluminum channel stock and weld some standoffs to the existing cake pan, then mount it. I don't even think closing the small 3/4" gap around the fan is all that critical for cooling, especially when the aux fan can already keep the engine cool all by itself and having a powerful e-fan will just add a huge capacity to the system.

Further, I'm hoping my low temp t-stat is here from Europe soon so I can re-do the cooling system and fan and my busted aux heater valve all at the same time and really be in good shape for summer. Hoping to keep temps about 25 degrees lower than stock from now on.

[fmzip]

While the baking pan is ingenious idea and probably less work, I like what I did and it's holding up well. Another advantage over pan is that aluminum sheet like mine is bolted to corners of shroud which makes it less likely to flex.
http://www.bimmerforums.com/forum/sh...most-completed

This is great too. Does the machine shop have a CAD file that you can share with the forum?? If they can make a Cad file, then anyone can take that Cad file to a machine shop and have them fabricate the exact piece.....

[geargrinder]

This is great too. Does the machine shop have a CAD file that you can share with the forum?? If they can make a Cad file, then anyone can take that Cad file to a machine shop and have them fabricate the exact piece.....

good question... in fact if someone found a shop (more a sheet-metal shop than a machine shop for those who delineate such things... but nitpicking) who would make one, I am pretty sure you could find buyers for a dozen or so pretty quickly... 540san you want to make a few bux for beer while helpin out your bros?

[sjenkins1129]

It was mentioned earlier that there may be some reliability problems with the Derale fan controller.

I used a Derale on a special project on a Jeep Cherokee to make an after run circuit for the existing electric fan. I could bore you with poor Chrysler design that created the need but I won't

The short answer is I DID HAVE PROBLEMS with the Derale. I am on my third unit. I did however figure out where the issue was coming from. The controller itself is water tight but the wire harness and connectors are not. My original install had the controller under the hood in a horizontal position with the relay tab sticking straight up, perpendicular to the roadway. When I would run through standing water or when I cleaned the engine looking for an oil leak, things would get wet in the engine bay. After speaking with a Derale tech support person, which by the way they were great to deal with, he suggested two remedies. The first was to mount the control with the relay tab oriented parallel to the roadway or even upside down so that water would not lay in the multi pin connector of the harness nor around the base of the relay and its contacts. The second was to eliminate the temperature sender connector and to hard wire and heat shrink the connection.

Apparently the water in and around the connectors, especially with winter/salty water here in Ohio, was creating strange and unintended current paths that were damaging the controller circuitry. This was evident by a wet controller chattering the relay and then it stopped functioning.

The third unit has been installed for a little over a year. I installed it with the relay oriented sideways/parallel to the ground and the temperature sender connector eliminated and hard wired. Previously the first two units wouldn't last 60 days.

I really liked the user who put his fan controller and all of his switching inside a project box that protected it all from the elements. If I had the Jeep project to do over or if I modify my 540i, I will use the project box method.

My 2 cents and personal experience.

[BMW540san]

This is great too. Does the machine shop have a CAD file that you can share with the forum?? If they can make a Cad file, then anyone can take that Cad file to a machine shop and have them fabricate the exact piece.....

Unfortunately, my neighbor who supplied the aluminum piece and cut it for me, has left the company and therefore lost access to machine shop which he was supervisor of. I honestly didn't think of asking him for the file which is great idea by the way.
On the other hand, the cuts are designed to fit particular Spal fan and while I'm huge fan of it (I have 3 identical Spal fans on all 3 of my bimmers) some people may prefer other brand.

- - - Updated - - -

good question... in fact if someone found a shop (more a sheet-metal shop than a machine shop for those who delineate such things... but nitpicking) who would make one, I am pretty sure you could find buyers for a dozen or so pretty quickly... 540san you want to make a few bux for beer while helpin out your bros?

I'll gladly help for free but check my response to fmzip which explains potential issue.

[fmzip]

It was mentioned earlier that there may be some reliability problems with the Derale fan controller.

I used a Derale on a special project on a Jeep Cherokee to make an after run circuit for the existing electric fan. I could bore you with poor Chrysler design that created the need but I won't

The short answer is I DID HAVE PROBLEMS with the Derale. I am on my third unit. I did however figure out where the issue was coming from. The controller itself is water tight but the wire harness and connectors are not. My original install had the controller under the hood in a horizontal position with the relay tab sticking straight up, perpendicular to the roadway. When I would run through standing water or when I cleaned the engine looking for an oil leak, things would get wet in the engine bay. After speaking with a Derale tech support person, which by the way they were great to deal with, he suggested two remedies. The first was to mount the control with the relay tab oriented parallel to the roadway or even upside down so that water would not lay in the multi pin connector of the harness nor around the base of the relay and its contacts. The second was to eliminate the temperature sender connector and to hard wire and heat shrink the connection.

Apparently the water in and around the connectors, especially with winter/salty water here in Ohio, was creating strange and unintended current paths that were damaging the controller circuitry. This was evident by a wet controller chattering the relay and then it stopped functioning.

The third unit has been installed for a little over a year. I installed it with the relay oriented sideways/parallel to the ground and the temperature sender connector eliminated and hard wired. Previously the first two units wouldn't last 60 days.

I really liked the user who put his fan controller and all of his switching inside a project box that protected it all from the elements. If I had the Jeep project to do over or if I modify my 540i, I will use the project box method.

My 2 cents and personal experience.

Great info! Time to remount mine or silicone the connector head

[jstern]

Great info! Time to remount mine or silicone the connector head

+1. Even though the Derale controllers have been on my wife's and my car for 3 1/2 and 2 1/2 years respectively with no problems (relay tabs are mounded parallel to the ground), it's better to be safe than on fire. BTW I do wash engines regularly.

[crashgordan]

still following... good stuff

[AK_5eries]

I read through the reviews on the 20" cake pan on Amazon. It is actually 20.5" outside diameter.
V8 shroud is 19.8" inside diameter. I don't think it'll fit

Maybe those people were measuring the lip as part of the diameter?

[crashgordan]

Got my parts installed on the new box.

Planning to do the install tomorrow

It's been a few months. hows it holding up??

[fmzip]

It's been a few months. hows it holding up??

It's working perfect.

Today I decided to wire up the over ride switch since I am going on a 300 mile trek soon. Took the same 12v hot wire that I used to the Derale and split it "Y". Then I fed the 12V to one side of a switch. Then took the green wire, fed that to the other side of the switch. Turned the switch on, the fan wouldn't turn on as it should with the over ride switch.

Tested everything with a meter, I have 12v across the switch when I flip it on. Ideas?? Pretty straight forward directions

http://static.summitracing.com/globa.../der-16749.pdf

[JimLev]

Did you have the ignition on?
Check out the Q and A at the bottom of page 2 in your link.

[fmzip]

Yes, ignition on.........

I read the questions and answers Jim, Doesn't look like I am missing anything.

12v and green wire should turn the fan off with all the other wires still connected, correct? Just would like a manual over ride if this thing were to ever die. Put some cutters in the trunk, could always just take power directly to the fan in the worst case scenario but I'd prefer to have this thing work.

Q: Why doesn’t the electric fan turn on when I turn on the A/C or Manual Switch?
A: To quickly test the Manual Override Circuit, disconnect the Green wire and run a jumper wire directly to the Positive (+)
terminal on the battery. Electric fan should start immediately. If fan started reattach the Green wire to the proper (+) wire
on the A/C clutch or Manual Switch.

It's basically saying remove the switch you just installed to see if the switch is defective. I have a switch between the 12v and green, it should work. And Yes the switch is on

Might be a good excuse to try that Hayden 3655 controller..

[Kenny1958]

I bought this controller for my 540 as yet it's untested but will be soon.

[16valex]

Took the same 12v hot wire that I used to the Derale and split it "Y". Then I fed the 12V to one side of a switch. Then took the green wire, fed that to the other side of the switch.

One of these three things can occur.
- Bad switch
- Blown fuse
- Defect controller.

[fmzip]

I tested the switch, it works.
There is no fuse, straight hot to the green wire.
The controller still works fine other than this green wire.

Guess I will call Derale tomorrow