[Paulw]

Hi was thinking of running a 16' low profile SPAL fan on mine and was wondering if anybody has a thermo fan installed on their jimny and what size it is and which controller they are using? I'm thinking of using the Daviescraig electronic controller.

[Gwagensteve]

In place of the stock fan or in addition?

Steve.

[Paulw]

In place of the clutch fan

[Gwagensteve]

Don't do it.

Odds are you'll have overheating problems. On top of that, you've increased load on the alternator, and introduced control/switching gear which all has its own reliability factors.

Mechanical fan FTW. The simplicity and reliability of the mech fan outweighs the small advantages of a thermo.

Steve

[droverdave]

yer theres not much advantage really. Unless you are forced too due to some sort of engine conversion that doensnt allow it.

The main thing i think that makes a mech fan better is the fan shroud. Most aftermarket fans you see are just slapped on in the middle of the radiator and the edges dont get any air flow to them.

I installed a thermo fan on my old ke70 corolla, picked it up dirt cheap at a repco sale i think so i gave it a go (just slapped it on the middle of the rad). I mean it was good in that it did its job, but it gave me one more thing to worry about (wiring etc). If i was to ever use an electric fan again id get one off a FWD car that has the shroud built into it and cut it to suit my radiator, and then use the thermo switch from the same car and somehow put it into the cooling system.

Thermo fans also make a hell of a racket compared to a mech fan. 80s cars shouldnt sound like they have a jet turbine in the front end.

[Paulw]

Not too concerned with it overheating as I've used thermo fans in the
past without any troubles, and done 100,000+km using after market kits before
Plus was thinking of taking the clutch fan as a backup when I do bigger trips.
Also looking at the shroud there already I can modify that to suit. I know they can
make a bit of noise but I don't mind that.
Was really after if any body has fitted one and what setup/size they used.

[Gwagensteve]

So what's the advantage?

Especially if you are going to carry the mech fan with you "just in case"

Modern viscous fans gave stuff all effect on power output when the engine is in normal operating temperature range.

I have thermos on my car, because the radiator is behind the cab, but where possible a viscous mechanical fan is preferable.

Steve.

[31zook]

If you want the most effective fan ever, put some TEK screws through the clutch

[droverdave]

On the other hand, most cars these days do come with thermo fans, so setup well, they do give good service.

As for sizes,sounds like its going to be determind by to what you can fit with your modified shroud.

[Paulw]

Stock fan is pretty small maybe 13inch,
dosn't cover much of the radiator

[droverdave]

Well 14" seems to be an available size of thermo fan. Hack the shroud to fit?

[Gwagensteve]

Manufacturers really tried everything other than thermo fans initially - Clutch driven mechanical fans (Mercedes) Hydraulically driven mechanical fans (Toyota) are two examples.

Paul, I'd be very concerned that removal of the stock engine driven fan will void engine warranty. If I was a manufacturer, I wouldn't warranty an engine that the owner had pulled the stock fan off of.

Is there a problem with the existing engine fan? What's the motivation for removing a factory-engineered solution (that's radiator/shroud/fan and fan hub - they're all a system) and adding a thermo? Is it for perceived engine performance increases?

Steve.

[2stroker]

Steve just asked my question, what is the motivation, what do you hope to achieve.

[Paulw]

LOL I don't think my much of my Jimny will still be covered under warranty any more especially the motor. My motivation is gains in performance and economy.

[atari4x4]

should have just bunged the m18 in there instead of the m15

[Paulw]

atari4x4 wrote:

should have just bunged the m18 in there instead of the m15

[Gwagensteve]

You'll get VERY little gains in either.

Of course you'll "notice", but I doubt a dyno could tell.

When the engine is at temperature, the fan offers almost no resistance.

The "huge" claims for power and economy when swapping to a thermo are generally based on cars with heavy, fixed blade fans. The gains are much smaller with a viscous fan.

Steve.

[pezz]

Paulw wrote:

My motivation is gains in performance and economy.

stock wheels and tyres, stock height suspension will do that for you
then if you sell your aftermarket wheels, tyres, and suspension you will have a pocket full of cash for a m18 for more power and 7 hi clones to get the economy back

[Paulw]

Look if any body can has got an answer to my question(which is the topic title)
then please give me your input especially if you actually own a Jimny. If not then fuck off
This wasn't posted in he normal Suzuki talk section

[Gwagensteve]

Looks like you don't have much support for this modification. Get stuck into it and prove us wrong.

Steve.

[Rhinoman]

Gwagensteve wrote:

When the engine is at temperature, the fan offers almost no resistance.
The "huge" claims for power and economy when swapping to a thermo are generally based on cars with heavy, fixed blade fans. The gains are much smaller with a viscous fan.
Steve.

I doubt if it will be noticeable. I run an electric fan but its primarily so I can turn it off when wading.

I found the shroud to be a bit of a nightmare as it trapped mud which was impossible to clean out so I ended up with a very small area actually flowing any air, removing it didn't make any noticeable difference to engine temperatures but it tends to be cooler over here most of the time.

[christover1]

I split my shrouds, makes them easier to remove the top half for washing out mud.

[Red89]

The biggest I could fit in my Sierra is a 14" $100 cheapo from Supercheap being controlled by a mechanical DC switch. Considering the switch is completely open and exposed to the elements, gets covered in dirt, mud, grease, salt, water etc and hasnt failed once in the 7 years it has been in there. With it set to come on around 1/3 up on the dash gauge when it was being daily driven the fan rarely came on as the air flow was sufficient to keep it cool, the only time it has boiled was during a comp and the rad was full of mud but it was simply a matter of swapping the wires over on the switch so that it bypassed the thermostat and ran straight off the battery. I dont run a shroud either just attached the fan to the rad and again have had no problems. The only real benefits I got from it were it meant the motor could actually warm up to normal running temp instead of sitting just above cold and when the water was deep enough the engine didnt have to propel an engine fan through the water.

[Paulw]

Thanks Red89 for the info. Did the thermofan cover a large portion of the radiator?
and did you have much clearance from the front of the engine?

[zukenutter]

If you guys have a look through Paul's build you'll see that he is working through a series of tweaks, all of which will make only small differences, though the sum of them combined will add up. It's great to have some input from someone who's keen to experiment and introduce some insight from a different school of thought. Most people would not be bothered and maybe not into performance enhancement which is fine too but hi clone type comments are pretty pointless and unproductive.

[Chop]

zukenutter wrote:

If you guys have a look through Paul's build you'll see that he is working through a series of tweaks, all of which will make only small differences, though the sum of them combined will add up. It's great to have some input from someone who's keen from boostcruising. Most people would not be bothered and maybe not into performance enhancement which is fine too but hi clone type comments are pretty pointless and unproductive.

Sorry couldnt resist Spose it depends on it your heading for a ricer road car?

[Red89]

Paulw wrote:

Thanks Red89 for the info. Did the thermofan cover a large portion of the radiator?
and did you have much clearance from the front of the engine?

No worries mate, the fan covers around 80% of the radiator and I had to space the radiator forward around 10mm to get around 10 mm clearance to the pulley on the motor.

[pezz]

zukenutter wrote:

If you guys have a look through Paul's build you'll see that he is working through a series of tweaks, all of which will make only small differences, though the sum of them combined will add up. It's great to have some input from someone who's keen to experiment and introduce some insight from a different school of thought. Most people would not be bothered and maybe not into performance enhancement which is fine too but hi clone type comments are pretty pointless and unproductive.

are you saying hi clones dont work?

[zukenutter]

^^ yeah of course they work and six works fantastically but seven is just stupid

[pezz]

ahh... fairynuff