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Discussion about cooling, thermostat etc...
vlad01 - June 28th, 2010 at 09:56 AM

Ok after long time looking into cooling fans and stuff I come to realize that nearly all after market cooling systems don't have some sort of thermostat. Now I see this as really bad engineering. After checking out GBE website, they also had the same view point as I do. So whats the deal? Also a question came to mind? If the porsche 911 cooling systems are what after market fans are based off, then what does porsche use to control air flow thermostatically?

Also another thing I come across is that the stock dog house beats nearly all after market fans/shrouds? how come? because VW designed the their cooling shrouds to direct air via vortcities (spelling?) to key air at exact velocities. I bet most of these designers of the after market coolers don't have a degree in fluid dynamics.

So makes me wonder then what works properly and has thermostat control? Or do I have to go the drawing boards and make something my self?

Also another thing that falls into this subject is full flow oiling and its effect on the relief valves vs bigger oil pressure vs different viscosity vs different temps .Adding oil thermostats and other things too.

So dam confusing coz one day when I do go to build a hypo donk every thing MUST be done right otherwise I am going to be pissed. :lol: engine is like a chain. just think about it.

Vlad.


Joel - June 28th, 2010 at 01:02 PM

Its all down to cost cutting and people being cheap.
It would cost more than double to manufacture the flaps with the shroud and Not many people would pay $200+ for a quality shroud with flaps when they can buy a cheap POS by empi for $50


New OEM style bellow thermostats havent been availble for decades and those mexican ones arent fail safe, but there is a member on thesamba who can rebuild old german ones if theyre just punctured and lost their fluid.


mechanics who dont know vws real well think cos their aircooled lawnmower or motorbike doesnt have a 'stat a vw doesnt need one either

I've got a working setup up on my 1776 and my spare 1600 and even around here in summer they still open and close at low speeds and I've also noticed the main difference they make is to fuel economy especially around town and the heaters work so much better with them


vlad01 - June 28th, 2010 at 06:21 PM

I am thinking with a future planed boosted efi engine, I want to use this.

http://www.laperformance.co.uk/blog/?page_id=260 

The horizontal fan as it overcomes many of the problems faced by upright 911 fans. Big one being uniform increased air flow, also this would suit a notch better than upright. Pretty sure most US made 911 fans suffer problems with
air direction and turbulence. A challenge with these kits on the link ^ would be thermostats.

Do you have a pic of what the type 1 air flaps look like? Just to get an idea what the setup is like? I have no idea as I never owned or worked on a beetle.


Joel - June 28th, 2010 at 07:09 PM

I dont wanna seem like I'm pissing on your parade but before you hand over a huge wad of cash for one of those setups I'll just input my $0.02

Those setups work alright in a bug or a kombi but all aircooled VW engines be it upright type1 or pancake type3 or type4 have one thing in common with the cooling system, they are all setup so the fan only pulls in cool fresh outside air rather than hot recirculated air from the heads and exhaust

bug and kombi by sealing off the top of engine and ducting in cold air through vents up high and type3s by ducting cold air through the vents in the sides straight to the fan intake

with that setup theres a good chance it in slow moving traffic it will recirculate hot air from the heads and exhaust and also turbo in your case

I may be way off with that statement but thats always been a problem with type3 and type4 engines in buggies and bajas, the fan intake is down low at the back of the engine so its always sucking in hot air off the heads and exhaust

Heres some pics of my 1776 thermostat setup
type3 and 4 are a similar theory just different layout


vlad01 - June 28th, 2010 at 07:59 PM

traffic? there is no traffic hear. I would run more into an issue of high speed vacuum behind the rear window rather than sucking in warm air from around the engine. Type 3 cooling system can not be used at all in my planed setup. a flat fan like that one I linked you to would be the best option as it should sit below the deck and get little bit and get fresh air from around. but type 1 cooling well.

this says more than enough.

http://i108.photobucket.com/albums/n23/THESHOP13/notch2.jpg

there was a pic and some vids of a notchback running the horizontal 911 fan and looked quite promising.
I will post it if I can find it :lol:


vlad01 - June 29th, 2010 at 12:39 PM

here we go.
took me 8 hrs to bloody find this. haha no wonder its in German. :crazy:

http://www.youtube.com/watch?v=fwbreVMgc2I&feature=related 


Joel - June 29th, 2010 at 12:59 PM

people have used type1s and porsche fans in type3 before, its not that it doesnt work, its just not a key ingredient for long living engine

most of them are all for show or a few strip runs so its no big deal but if i was dropping that sorta coin for an engine I'd want maxium life span from it

have a hunt around the forced fed and fuel injection forums over at shoptalk, I've seen a few f**k off EFI turbo setups with stock type3 cooling


vlad01 - June 29th, 2010 at 01:14 PM

I have been snooping around those forums. that how i got the idea of the flat fan as some people in that forum were using it and found it to be the best setup.

so if thats the case then that is ones problem out of the way. next one is the issue of it running too cold and long warm up time. thats is to say if the these German fans kits don't have thermostat system , which
they may well already have?


68AutoBug - June 29th, 2010 at 06:32 PM

Quote:
Originally posted by vlad01
Ok after long time looking into cooling fans and stuff I come to realize that nearly all after market cooling systems don't have some sort of thermostat. Now I see this as really bad engineering. After checking out GBE website, they also had the same view point as I do. So whats the deal? Also a question came to mind? If the porsche 911 cooling systems are what after market fans are based off, then what does porsche use to control air flow thermostatically?

Also another thing I come across is that the stock dog house beats nearly all after market fans/shrouds? how come? because VW designed the their cooling shrouds to direct air via vortcities (spelling?) to key air at exact velocities. I bet most of these designers of the after market coolers don't have a degree in fluid dynamics.

So makes me wonder then what works properly and has thermostat control? Or do I have to go the drawing boards and make something my self?

Also another thing that falls into this subject is full flow oiling and its effect on the relief valves vs bigger oil pressure vs different viscosity vs different temps .Adding oil thermostats and other things too.


Vlad.


Hi Vlad
Yes,
I've read that the aftermarket fan housings are rubbish...
If You look closely into a VW fan housing You will see all the design work they have done...

I had a new type of thermostat I bought from CBperformance in the USA... but can't find the rod...
I also have an original beetle thermostat assembly but can't find the rod.. lol

I would put it back in if I could find a rod.. lol
as its 6C here at the moment.. and having no thermostat isn't good... IMHO.. plus it takes ages for the heater to get hot... lol

Gene Berg did a lot of testing and said the doghouse fan shroud is the best to cool the heads and the next best is the non doghouse fan shroud... He tested for 20-30 years...

thermostats and the air flaps should be used...

LEE


vlad01 - June 29th, 2010 at 07:38 PM

so what are the non dog house the gene tested? those 911 fans are good if you get the proper ones with internal air deflectors and guides. As always the German made 911 fan kits are exactly done like that so they perform good.

Obviously you would not buy a US(china made) 911 fan. aka scat 911 fan kit. its garbage. I never used one but you can tell straight away buy just looking at them what the problems will be.


matberry - June 29th, 2010 at 08:00 PM

Quote:
Originally posted by Joel
people have used type1s and porsche fans in type3 before, its not that it doesnt work, its just not a key ingredient for long living engine

most of them are all for show or a few strip runs so its no big deal but if i was dropping that sorta coin for an engine I'd want maxium life span from it




Joel is on the money here.
The air intake must be only fed cool air. Just because you see pics or read somewhere it's been done doesn't mean it'll be ok here is Oz with our summer temps, or that the engine lasts over 100 000km..... Cooling system is a major system derectly protecting your engine...without it the engine is toast.

Thing with air cooled, is they keep on going, if it was water cooled, when they overheat, they soon let the driver know they are complaining with steam going everywhere, or water getting into the oil or whatever, but not with air cooled. They just get hot. Sometimes they just keep going but the fatigue that occurs isn't always evident, for a while anyway.


vlad01 - June 29th, 2010 at 08:20 PM

this pretty much sums it up.

http://www.tunacan.net/t4/tech/upright-911.shtml 

I figured out a great idea. you know the deck in the type 3 vw? well you could custom make a large vent in the deck and run a big aluminum duct straight onto the dog house. like this :yes::tu:

http://i1015.photobucket.com/albums/af278/vladk01/dogcooler_mod.png


matberry - June 29th, 2010 at 08:27 PM

That will still draw in air that has been through the cooling system. I'd look at sealing similar to a beetle around the engine and keeping the intake unrestricted, pipes in front of he fan will reduce the actual output significantly.


vlad01 - June 29th, 2010 at 09:36 PM

no it wont. a 14 inch air duct by say 60cm long wont be restrictive. the stock air channels from inside the guards are far smaller than that.
secondly, the air being drawn in is fresh cold air from a completely isolated source, you know? front area around the gear box. type 3s dont have a fire wall like beetles do.

lol isn't the drawing clear enough?


68AutoBug - June 29th, 2010 at 11:49 PM

Quote:
Originally posted by vlad01
no it wont. a 14 inch air duct by say 60cm long wont be restrictive. the stock air channels from inside the guards are far smaller than that.
secondly, the air being drawn in is fresh cold air from a completely isolated source, you know? front area around the gear box. type 3s dont have a fire wall like beetles do.

lol isn't the drawing clear enough?


Yes,
looks good to Me
seeing how not much air can come from the air vents in a type 3

it always amazed Me how the notchback got enough air from below the rear window..!!!
but they do have a nice sized fan... lol

so, a duct like that into a type 1 engine and fan housing etc..

should get enough air... when driving along but when stopped??? I don't know..
the longer the ducting the better..

I can see what Matt is saying, the beetle engine bay is isolated from the heat under the engine where Yours would not be... and that is a LOT of heat under a beetle engine..

cheers

LEE


1303Steve - June 30th, 2010 at 09:11 AM

Hi

I going to have look at Valla for the bits to finish the thermostat on my sons bug, just need one flap from memory.

Now that we will soon have no heaters I was looking at buying a 36 hp style fan housing, but they seem to be rubbish.

Has anybody seen a step by step web page on cutting off the heater outlets and narrowing a stock dog house fan housing?

Steve


matberry - June 30th, 2010 at 09:21 AM

Quote:
Originally posted by 1303Steve
Has anybody seen a step by step web page on cutting off the heater outlets and narrowing a stock dog house fan housing?

Steve

No but done it a few times, easy when your in love with your angle grinder. :love:


Joel - June 30th, 2010 at 10:03 AM

Steve, there's a guy on VZi thats got a few pics of when he cut down his stock doghouse one but I've also seen I think on thesamba someone that used the front skin of an original 36hp and mated it to the rear section with the vanes of a OEM doghouse shroud

Finished result looked like all the 36hp shrouds on the marke but had the qulaity of an original


vlad01 - June 30th, 2010 at 10:07 AM

after snooping some more last night. I figured I will use jake raby's DTM cooler. I far as what I read from him, they dont have a thermostat but he says a stock one can be fitted
with some modifications. its a work of art the DTM. Nothing short of amazing :)