Disassembling viscous fan

[MattF]

Fit one in front of the rad, and the other in the middle of the bonnet!

Will you please stop encouraging me, Vince. Tempting thought, though.

[BUSHWHACKER]

Another thing I meant to ask, does anyone know why some electric/viscous
fans have staggered blades, i.e: not all blades are evenly spaced around the
hub? I would've thought it would have caused an imbalance, but there seem
to be quite a few vehicles with this design. Just curious.

Maybe it's to let more air flow through them when they're not operating?

[BUSHWHACKER]

From what I could gather, the LC and Surf viscous clutch unit are the
same or similiar, but the LC fan has eight blades with a steeper pitch
than the seven bladed fan of the Surf.

Don't forget that other Toyota import, the Estima has the same 2.4 engine as the Surf so look out for these as well when at the breakers.

[MattF]

Maybe it's to let more air flow through them when they're not operating?

Possibly. It just seems weird when you look at them. This one on ebay is
a prime example:

http://cgi.ebay.co.uk/XJ6-JAGUAR-SER...QQcmdZViewItem

[MattF]

Don't forget that other Toyota import, the Estima has the same 2.4 engine as the Surf so look out for these as well when at the breakers.

Now that I didn't know. I'll keep my eyes peeled next time I'm doing
acrobatics between the car corridors.

[Chillitt]

Possibly. It just seems weird when you look at them. This one on ebay is
a prime example:

http://cgi.ebay.co.uk/XJ6-JAGUAR-SER...QQcmdZViewItem

its to stop them resonating and making a din. er like locked up surf fans do..

[MattF]

its to stop them resonating and making a din. er like locked up surf fans do..

Now what type of daft sod would do something like that?



















Oh,.............. bugger.

Kept wondering about that. First time I saw one I thought it had lost
some fins. Then realised it was actually meant to be like that.
Must admit though, a locked fan does make a nice beasty air roar
when you're accelerating.

But, me being me, set myself off being curious about this electric
fan inconsistency. Can't see why an electric shouldn't be able to
cool practically as well as a viscous. If a decent flow rate is there,
why should electric fans seem to be less able to keep things cool?
I mean, John's having problems since fitting the electric, and on the
Aussie site, apparently it's classed as a less than ideal solution there.
Someone else on here, (I think it may have been Andy), also had
problems when using an electric and went back to viscous. It's gonna
bug me now until I give it a try. (I'll never learn). Only reason I can
think of is that the electric fans are usually setup to kick in at around
thermostat opening time, so possibly trying to cool too late in the
process. I'll be trying this one running permanently, not temp sensor
coupled, if I manage to get it adapted to fit, so hopefully my theory
will be correct. If not, I'm buggered.

[MattF]

Just checking before I start the hard way, does anyone have dimensions
for the Surf radiator, including measurements for fixing centres? Or the
same info as above for the shroud?

[mud skipper]

mattf
STOP!!!!
an electric fan cannt run contiunously as it will burn out unless it is from something thats designed to run for ever,


i have just ordered a new viscous fan from toyota, no electric fan for me again. will post you an update when i have test run it.

[MattF]

John, is that info that Kenlowe supply with their fans? A fan should be able
to run for an indefinite period without problems, unless the motor housing
or windings are designed for intermittent use. I'll double check, though, just
to be on the safe side. Wouldn't surprise me if automotive units are designed
differently.

Out of curiosity, does the Kenlowe fan require the fan shroud to be reinstalled,
or does it have its own shroud?

[mud skipper]

John, is that info that Kenlowe supply with their fans? A fan should be able
to run for an indefinite period without problems, unless the motor housing
or windings are designed for intermittent use. I'll double check, though, just
to be on the safe side. Wouldn't surprise me if automotive units are designed
differently.

Out of curiosity, does the Kenlowe fan require the fan shroud to be reinstalled,
or does it have its own shroud?

no that info didnt come from kenlowe but they do say there is no warranty on a fan that is in continual use,
i donnt know of a fan that is continually rated other than brushless pc type fans and they only last a couple of years in a clean environment.......
the kenlowe does not require a shroud as it fits up to the rad and has a built in shroud/housing
hope that helped
im still unsure with mine, if the viscous doesnt cure it then mines up for sale and im back into boring cars, just found a 20ltr sri 140bhp estate vauxhall for 3500 on a w plate if all goes wrong this weekend.


any one want a kenlowe 17" suction fan only done less than 200 miles....

[MattF]

That's a bit of a sod if they won't apply warranty if it's run continuously. Just
checked on the Bosch GPB 12V units, and they have a S1 duty cycle, or
continuous:

http://www.boschmotorsandcontrols.co...riebsarten.htm

That would explain why they have an IP rating of 03. Must be self cooling units.

The specific motor isn't listed, but the GPB family is on this page:

http://www.boschmotorsandcontrols.co...ent/30-100.htm


I still think you'll notice a difference with a viscous fan, purely down to the
fact that the Kenlowe instructions about when the fan should switch in seem
very debatable. Have you still got your original fan shroud, BTW? If so, is
there any chance I might be able to sweet talk you into taking some
measurements of it? Pretty please.

Have you tried doing that test run where the temp rose with the fan permanently
on? Could be worth trying it just to see if it does make a difference. I know it's
not how their fan is designated to be used, but at least it might clear up whether
it is just switching in too late.

Another edit: With those computer fans, they usually die due to the bearing
running dry or getting clogged, (on a decent quality one). The type in standard
pc fans is just a brass bush which gets clogged and tightens the shaft up. The
better quality ones can be stripped down, cleaned and lubricated, and they'll
usually work fine.

Sorry. Irrelevant I know, but I just had to throw a piece of useless trivia in.

[mud skipper]

nice to see you have found a fan that will run, as far as mine goes i dont use the surf every day so my testing isnt fully thorogh, becouse of the warranty i havnt tried it in continus mode, i mite try tomorrow night after you ring me with the measurements you want, i will pm my number to you now

[MattF]

Another quick brainpick chaps. Does the fan shroud NEED to cover
all of the radiator core? Just trying to determine whether some creative
fabrication is required for this electric fan shroud. Measurements of the
original are approx. 50cm top to bottom, 55cm left to right. New shroud
measurements are approx. 42cm top to bottom, 39cm left to right. So,
without alterations, would have a gap of approx. 8cm bottom, 8cm
left/right of radiator. Too much, or within usable limits? (Thanks to John
for the measurements off the shroud, greatly appreciated).

Cheers.

[BUSHWHACKER]

Woo hoo!! page 24.