Thermo fan, worth it?

Nissan Navara Forum

Help Support Nissan Navara Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Joel

Member
Joined
Nov 26, 2011
Messages
18
Reaction score
0
Location
Northen Rivers NSW
Hi all,

Has anyone removed the stock fan and clutch on a non turbo TD27 and fitted a thermo fan?
Just wondering if it's worth the effort and expense.

I rebuilt the entire cooling system about 2 years ago (new rad, hoses, 'stat) only thing I didnt touch was the waterpump and fan.

The waterpump is original and has never been changed in 300+k and is starting to leak around the gasket and my fan has cracks between all the blades on the hub.
I know my fan clutch is just about ****ed, it has a whine/roar like the bearings or bushings are going bad at about 2000rpm and doesnt engage the fan fully.
Not surprising with the age and KMs.

I've got a new water pump/fan clutch to chuck on but just wondering if its worth the effort of fitting thermo fan or should I just replace the stock fan and leave it all as the dr intended?

On some of my other cars I got excellent power increase and noise reduction fitting thermofans but they were older direct drive non clutched fan setups which are power sapping something major.

I dont know if I will see much noise reduction or power freed up with it being a clutch type fan to justify the swap but would like to hear any opinions

Cheers
 
Thermo fan should keep the coolant temp ok but from past experience the fan more that just cools the coolant, it keeps under bonnet temps at a reasonable level.
 
general rule of thumb is mechanical fan beats electric fan especially in 4x4 situations.
 
Thanks guys, I'll keep it simple and just get a replacement stock fan blade then.

I don't remember the fan in my D22 being that loud so maybe I'm just over thinking things.
 
Yeah I was thinking of dumping the stock fan on my Z24, as the blade chop alone whirs like buggery. The noise as the revs pick up cancels out anything else the engine bay emits; some pedestrians even stop and look to see what all that damn rukus is about.

Hmmmm, free up only a couple of extra newtons and considerably reduce the noise output; or pump gallons of tainted air across a hot little iron Japanese watercooled bastard. Maybe venting the bay through the scuttle panel or hood could offer a venturi effect, and the timing light wouldn't get clipped by the fan blades....
 
Hey guys,

just as a follow up to this, I ended up replacing my waterpump and fan a few months back (vids on youtube if anyone is interested) and I just fitted a replacement stock fan.

by the time I bought a reasonable quality thermofan and a controller to operate it the cost was going to be way more than just buying a new stock fan blade.

That roar/howl I was getting has shut up a bit but its running much happier now and doesnt get hot under load anymore
The bi metal spring on the old waterpump had siezed up and wasnt engaging the fan fully.

I also noticed there was no way of removing the clutch hub from the water pump which would have made fitting a thermo fan less worthwhile.


Wally, sounds like your fan clutch may be stuck fully engaged, they don't normally make that much noise when the engine isnt hot and the fan is just free wheeling.
 
Hey hey, cheers Joel, I'll get in there and have a tinker over the weekend (weather/wife permitting). Good on you for sorting yours, and possibly mine, out!
 
Fan Clutch Maintenance!

I really have not looked, as mine seems to be O.K. for now," but" can oil or other
Lube be used to help the Fan Clutch last longer, and save this old Fart enough for
yet another Whisky, I am thinking of our old "AJS" Motor Cycles" Primary Drive and Oil bath clutches, worked a little like a "Steam Turbine" except useing Oil instead of Steam,LoL!

Has anyone opened one of these up to see what they are about, maybe drill a
hole in the Hub area and fit an Oil filler cap to keep it lubed, With that, I will now
crawl back into the Bildge for my Cup of Tea!

Highway Man!:yeahright:
 
I really have not looked, as mine seems to be O.K. for now," but" can oil or other
Lube be used to help the Fan Clutch last longer, and save this old Fart enough for
yet another Whisky, I am thinking of our old "AJS" Motor Cycles" Primary Drive and Oil bath clutches, worked a little like a "Steam Turbine" except useing Oil instead of Steam,LoL!

Has anyone opened one of these up to see what they are about, maybe drill a
hole in the Hub area and fit an Oil filler cap to keep it lubed, With that, I will now
crawl back into the Bildge for my Cup of Tea!

Highway Man!:yeahright:
Toyota sell viscous hub fluid. If you feel the need to change it and don't feel intimidated walking into one of their dealers then it is available...
 
Fan Clutch Lubes!

Good Morning Bods,
Thanks for your reply, I might do just that, to find if it is worth while, and find out
about viscousity, price, availability and soforth, to see if the Item is worth the
time against buying a new Fan Clutch every year or two, really it is more a matter
of understanding another weakness in my Ute and being able to create a better
rachiem of Maintenance, to run her cheaper and better each year, as well as put up with a Wife who hates the thought of spending time as well as money working on it, which I have enjoyed doing so far, I have always thought prevention is better then cure with most things!

I'll post a return Thread on what I find out in case others have an interest as well!

Regards,

Highway Man!:deadhorse2:
 
We replaced our viscous hub (fan clutch, fluid couple) not that long ago and I've discovered another neat test if you've got the ears for it.

We drove along heading to Mt Panorama (I worked at the race track over Easter) and noticed that on downhills, at first you could hear the rushing sound of the cooling fan working hard and then see the coolant temp dropping rather nicely. As it reached 91C the engine went quiet as the fan clutch was released!

The corollary of that is that when you start working the engine, you'll faintly hear the note change as the fan engages (the roar of the diesel and my new-found turbo whistle* did make detecting this difficult) so if you don't hear it engage in the high 90s, and disengage in the low 90s on a downhill, chances are yours needs checking.

I've got a spare now, which I intend to pull apart and rebuild. I tested it with a paintstripping gun which does make it work (although not fully), but I need to throw my infrared thermometer at it to see when it triggers. Might be a new thread on this topic, because it's important particularly if you're towing - and especially if you're towing heavy.
 
Filling Fan Clutch!

Good Evening Al'

Do the clutches have a refill hole or screw to top them up or do I have to take the unit off altogether and drill it and tap the hole for a screw type Plug, then top it up with a Medium Viscosity Oil to get what we requirer?!

Regards,

Highway man!:adminpower:
 
They don't have a hole that I'm aware of yet, and it's wise to not drill one in there. They are balanced so that the fan rotates smoothly. If you off-balance it, the fan will be off-balanced and the blades could crack.

There are only two suitable fluids that I know of. One is the viscous hub fluid from Toyota (the only company to sell the stuff that I've heard of) or silicon oil for radio control car shock absorbers.
 
If you're taking yours off, pay close attention to the blade roots. We've had a couple of people report cracks appearing there. If the crack flexes when the fan is pulling hard, the blade tips will edge forward - possibly into your radiator.
 

Latest posts

Back
Top