Blue fan clutch mod...Thread has gone to hell, read at your own risk (2 Viewers)

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Along the lines of draining the clutch, I'd think that placing the parts on rack of some sort with a catch pan and put in an oven at say 150* would go along way in getting that stuff to drain more completely out of the base since that side doesn't come apart.

And I'm not against the thicker oil, but for me it was staying as stock as possible unless there was a need for a change. It's still early with this setup as I've only got one loaded drive during hot weather under the belt. A few more trucks and some more miles might reveal a need for heavier oil.
 
landtank said:
Along the lines of draining the clutch, I'd think that placing the parts on rack of some sort with a catch pan and put in an oven at say 150* would go along way in getting that stuff to drain more completely out of the base since that side doesn't come apart.

Agree, heat helps speed it up, also moving, changing the angle slightly during the process. I have used coffee cans, foam, plastic picnic type plates, piles of rags, etc.

landtank said:
And I'm not against the thicker oil, but for me it was staying as stock as possible unless there was a need for a change. It's still early with this setup as I've only got one loaded drive during hot weather under the belt. A few more trucks and some more miles might reveal a need for heavier oil.

That was my thought when I saw the adjustable valve last year, your experiments show it has a positive effect and maybe all that's necessary in cooler environments.:cheers:

I talked briefly to the engineer about it, then sent him pictures of the clutch and fan with a note listing clutch capacity, our temps, etc. He was very impressed with the clutch and fan design, but said "what were they thinking putting 3000 cst in it? My recommendation would be some where between 15000 - 20000 cst, a good starting point for testing would be 17000 cst!":eek: His thought was that adjusting the valve was like putting a cooler thermostat in an overheating system, masking the real problem, an under performing radiator. It may get a head start on over shearing, but having the proper fluid would make for a more robust system.

He talked like a knowledgeable "car guy" but doesn't own a LC or ever worked on one and works for a company that sells silicone fluids, but he took the time to talk to me about our problem and sounded like he was interested in helping to solve it. I didn't get the impression that he was selling me and I think he realized that the quantities that I would buy wouldn't have an effect on their bottom line. So I classify his advice as honest, good input.

My thoughts on it; I have run thicker fluid in customers and my rigs with good results, all older style fixed valve clutches and 3.0's and 22R types, never a LC. So I don't have as strong of a "non stock" mod aversion and the fluid I have run up to this point has been from Toyota. My fan clutch was weak in my '90, 3.slow, Runner when I got it with ~100K, replaced the fluid with Toyota 10000 cst and never had a cooling, fan or clutch problem, wheeling, towing, etc. sold it with 200K, with the ring fan no less!:eek:

The part that I wasn't ready for, at all, was the 17000 cst recommendation!:eek: I was thinking in the 6K-10K cst range, so that is well outside of my comfort zone. But his argument for it sounded good and think I will start at 15000 cst and see what happens? Hopefully no exploded fans!:crybaby: :D
 
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I get it now.
All I saw was 4 separate posts. One was 111 the next was 222 and so on. LOL
Cheers,
Sean
 
Kevin, I've been first field tech on quite a few new to market machines over the years. And in a situation such as this where you have a high quality part that just doesn't seem to be doing the job quite right, I've come to a basic idea on this.

That is, the easiest least intrusive change that yields the greatest positive improvement is most likely at the heart of the issue.

Maybe that guy is right, but considering the fact that with no fan engagement at all it took 90*+ heat for my truck to approach AC cut off when unloaded says something about how well these systems are designed and how little help they need from the fan to control their temps.

I realise that you've been down this road before with other trucks but for me it would be nice to see you just tweak the timing as I have before upping the viscosity just for some continuity between what I've done and where you're headed.
 
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landtank said:
Kevin, I've been first field tech on quite a few new to market machines over the years. And in a situation such as this where you have a high quality part that just doesn't seem to be doing the job quite right, I've come to a basic idea on this.

That is, the easiest least intrusive change that yields the greatest positive improvement is most likely at the heart of the issue.

Maybe that guy is right, but considering the fact that with no fan engagement at all it took 90*+ heat for my truck to approach AC cut off when unloaded says something about how well these systems are designed and how little help they need from the fan to control their temps.

I realise that you've been down this road before with other trucks but for me it would be nice to see you just tweak the timing as I have before upping the viscosity just for some continuity between what I've done and where you're headed.

Rick I agree 100% with your method and like I said it may work in your area, time will tell.:cheers:

The rest of my rambling was aimed at others who may try this mod, if the clutch is older and weak, changing the fluid while it's apart is probably a good investment. If it's operated in a hotter climate thicker fluid will probably be beneficial, but is totally untested at this point.
 
landtank said:
B, I enlarged the pics and reworded it, let me know if it is still unclear.

Pics and wording made it more better. Thanks. :D

I'm a little behind you guys in understanding exactly what is happening. The 2 changes at once (temp adjust + more fluid) has me questioning if one or both are needed... I need to do some more reading of the prior threads. I get Kevin's idea of a heavier silicone oil and can see that logic.

I think there are a couple of guys with middle-east spec 1FZ-FE's. It would be interesting to see which fan clutch they get? (p/n if possible)

-B-
 
Beowulf said:
The 2 changes at once (temp adjust + more fluid) has me questioning if one or both are needed...

In that other long and winding thread you'll find that I actually did these two things separately. I advanced the timing, then added oil and then advanced the timing again. Adding the oil didn't produce any added benefit as far as lower temps but it didn't add any negatives either such as locking up the clutch when it wasn't needed.

The reason I left it in there is that the oil circulates through the clutch and the larger the oil capacity, the longer it takes to exchange the oil through the clutch and the more time it has to cool the oil. The same idea of having a large sump in the oil pan. The oil will cool better and last longer.
 
rick great job on this. i am confident this will become as widespread as the temp gauge mod once people figure out the benefits it offers

i have done the mod without adding oil and i think adding the oil is needed. without adding oil the blue clutch offers minimal cooling until it fully locks up. My old original fan clutch noticeably outperforms the new one even with the blue one advanced to 110. my blue one has less than 3000 miles and looks like new.

btw, the screws were exactly centred on my clutch and the clutch fully opened at 116 not 120, which could just be meat thermometer calibration. oil level was very slightly higher than Rick's when I opened it (just spilling over the shelf inside the hole) but it had several days to drain so even that may be a wash.
 
Likely a dumb question but....
If every thing is functioning correctly does the fan generally run at highway speeds or does the engine get enough airflow? Just wondering what the harm would be in rigging the fan to run all the time - just increased engine load?
 
MoJ said:
If every thing is functioning correctly does the fan generally run at highway speeds or does the engine get enough airflow?

Depends on the ambient temperature. Since this clutch is variable it will adjust the amount of drive depending on the temp of the air that has passed through the radiator which is dependant on the ambient temp.



MoJ said:
Just wondering what the harm would be in rigging the fan to run all the time - just increased engine load?

The fans we have on our cruiser's would be over driven at higher rpms. The clutch avoids this issue.

A solid driven fan needs to be a flex style so at those higher rpms it flexes under that load.
 
ugh! I've been following this post sense the beginning. Of course as always great info.
My question, if you buy a new (blue) clutch fan, do you have to add oil to it so it will work properly?
 
http://www.outerlimits4x4.com/PHP_Modules/phpBB2/viewtopic.php?t=71698&highlight=rebuilding+fan+hubs
I just rang the Toyota dealership here again to see if there were any changes to what I had passed on to some of you guys previously.
The only silicone oil sold here by Toyota is cst 10,000 for all fans regardless of what engine and model the fan is off diesel or gas/petrol .They say to completely fill the fan as I was told by Stewart's 4Wd approximately a year ago when I posted my pictures of the repair to the 2H fan.This seems to be advised by Toyota techs in the attached "outer limits" link also.Hope this is of some help.:cheers: .
 
nice work Rick :cool:

I need to try to find time to do this mod,
 
bigbrowndog said:
http://www.outerlimits4x4.com/PHP_Modules/phpBB2/viewtopic.php?t=71698&highlight=rebuilding+fan+hubs
I just rang the Toyota dealership here again to see if there were any changes to what I had passed on to some of you guys previously.
The only silicone oil sold here by Toyota is cst 10,000 for all fans regardless of what engine and model the fan is off diesel or gas/petrol.

That is the same info that I have heard, the 3000 cst is a US thing.

bigbrowndog said:
They say to completely fill the fan as I was told by Stewart's 4Wd approximately a year ago when I posted my pictures of the repair to the 2H fan.This seems to be advised by Toyota techs in the attached "outer limits" link also.Hope this is of some help.:cheers: .

The problem with that is that the valve no longer functions, the clutch is full on all of the time, been there, done that. If you open a new clutch it's no were near full, just the amount required to fill the reservoir.
 
bigbrowndog, do all your clutches look the same as the ones pictured in those links? I'm thinking that we have a different style over here and that the viscocity might not directly be relevant.
 
landtank said:
bigbrowndog, do all your clutches look the same as the ones pictured in those links? I'm thinking that we have a different style over here and that the viscocity might not directly be relevant.
Similar but not the same, each engine has a specific fan.:cheers:
I should also have said, The tech said they probably use a lighter oil because it does not get as hot over there, they get snow even. LOL.
 

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