New fan clutch oil replacement (red hub) - Update: swapped in stock green hub (1 Viewer)

[Infinity00]

Backstory:
Bought a new fan clutch a few years ago when I was rebuilding the engine. Alas, when I installed it I felt like it wasn’t pushing enough air so I put my old one back in. The old one spins a lot of air and roars most of the time, so it gets the job done but I wanted my new one in the cruiser to go with my new radiator.

New fan clutch, splitting and de-oiling:
Yesterday, I used a manual impact driver to get the overtightened screws out, then separated the half’s. The oil level only reached part way up when looking at the 4 holes. It wasn’t filled to the top, probably only half full. I wasn’t sure which half stores the oil though, the half with the valve or the half with the gasket groove and 4 holes. Flipped both upside down and oil only came out of the half with the groove and 4 holes. If I had to guess only 1 bottle’s worth came out, around 18 ml. I’ve read that two 18ml bottles is what he factory puts in but mine appears to only have had one.

Adding oil:
After draining the factory oil, I added around 18ml of 10,000 cst that I picked up from a hobby store and 15 ml of Toyota 3000 cst. This amount filled up the 4 holes completely to the top. I added a total of 33 ml and combined I should have a cst of something between 6000 - 6500 cst.

I don’t know if any oil is stored behind the closed valve in the other half. I had read about people heating it up in an oven and draining it, so I don’t know if it’s over full now (since I didn’t do that) but I’m going to run with it and see what happens.

 

[Infinity00]

Here’s what drained out of the brand new fan clutch (no heat applied to help), seems to be on the low side by about half the amount. Guessing the factory put in 1 bottle (18ml). It’s not much. I don’t know if you can tell by the picture.

 

[Infinity00]

Here’s the new oil I put in. I combined these bottles. I first added around 18 ml of 10,000 cst. That amount filled to the same level as what was originally in the fan clutch. Then I filled it to the top of the 4 holes with the Toyota 3000 cst oil. There was some left in the bottle and I am guessing it only took 15 ml. to fill the holes. Combined is 33 ml total. I’ve read factory is 2 bottles (36ml)

 

[FJ Silver]

That's great stuff. What made you decide to go with that viscosity? If you were to go with let's say 20,000 cst, would it engage the clutch earlier or later? Or is that not how that works.

 

[Infinity00]

I ordered the 3000 when I didn’t know Toyota offered 3 different viscosities. I believe they offer 3k, 6k and 10k. I was actually planning on just going with the 10,000 cst but I’ve read some people use the 3000 and some mix to get a value in between. It was more of a whim that I mixed them based on the fact that I didn’t want it on all the time, and I wanted something thicker than the 3000.

I wouldn’t go as high as 20k, 10k is plenty high from what I’ve read. People who live in hot places year round or are stuck in traffic in the heat use the 10k. I decided it gets only a little hot here in Colorado, and if I need to go higher than 6-6.5k, it will be easy enough to change out later.

If you want it to lock up earlier, the 80 series posts I’ve read, talk about it having an adjustable valve that will allow it to engage at a adjustable set point (I really want this), but I have no idea if it’ll fit on a 62. The red hub didn’t adjust as far as I could tell.

I think the thicker viscosity will lock it up better and stay locked up longer and give more air flow in hottest conditions, but not come on any earlier. But I’ve just inferred that from the million of other posts out there. I’m not the expert. There are you tube videos on the theory of operation that were informative. Let us know what you end up doing. Maybe the T100 has an adjustable one!

 

[Tools R Us]

Have done some playing with the red hub clutch without much joy, not a very powerful clutch. If it doesn't work for you, consider changing to the aqua hub from the FJ80. It's a solid clutch out of the box, if not enough, changing the fluid to 10K makes it damn powerful. Same spacing, pattern as the earlier F, 2F, etc, have put them on hard to cool FJ40, 60, 62, with good effect. They are commonly available, google; Aisin FCT-049.

 

[Infinity00]

Thanks for the tip @Tools R Us!

 

[FJ Silver]

Nice thanks, little over a $100 is not bad.

Curious about how your clutch will perform after the fluid change @evilorgoodtwin
I'll probably order the Aisin FCT-049 and swap it in coming week...

 

[LAMBCRUSHER]

I used an even mix of 15K and 7.5K- dont recall the final visc, but also timed the opening to start much cooler on my green hub. between the two, the temp never gets much above the second line, ac on, 110*, 70 mph...

 

[LAMBCRUSHER]

in my wifes fj62

 

[Infinity00]

@LAMBCRUSHER which hub is the green one?

 

[LAMBCRUSHER]

as called out above- the 3fe fj80 aqua green hub clutch; FCT-049

 

[LAMBCRUSHER]

there is a great write up in the 80s forum on retiming these clutches.

 

[Infinity00]

Yeah I’ve read those posts. I didn’t have enough forthought to think to use it on my 60. Wish I had before I bought the red hub. Good to know now tho, if it doesn’t work out I’ll pop one of those on.

 

[Infinity00]

I finally got everything buttoned back up with the new CSF2708 radiator, the new fan clutch with heavier weight oil, and the desmog. These are notoriously hard to burp but I’ve done it before and it wasn’t too bad this time. Took a long time but I finally got all the bubbles out by lifting the front end and running the heaters. It was stuck on 193 F the entire time - in a good way. I couldn’t get it to budge (the old radiator system all I had to do was turn off the heaters and give it gas for a few minutes and it would easily bump up in temp, not this one).

Decided to drive it - very hot today and driving up in elevation by 1000 feet put it to the test and it failed! It almost redlined, pulled over real quick and shut it off. The fan clutch spun way too easy in my opinion, so I’ll have to either try heavier weight or get the 80 green hub when I get a few dollars. Also, I found my vacuum line that opens the hot air flapper (HAI/HIC) had come off creating a large vacuum leak. I have gauges and I should have paid more attention to them!

After a little while waiting for it to cool, I finally re-attached the vacuum line and fired it up with all heaters blasting and it cooled off again. But when I pulled the line off my flapper, it slammed shut, I assume down blocking the hot air intake, so reattaching it opened it. This doesn’t seem right, it should have no vacuum with the engine hot and the door should have been blocking the hot air intake. I couldn’t see in the air cleaner horn to ascertain what it was doing, so I’ll have to investigate more with a flash light.

Summary:
1. Need to possibly burp it some more and/or do the temp sender yank to get coolant up into that area better
2. Might want to move my alternate temp gauge from the thermostat area to an area closer to the stock sender. The stock gauge went up very quickly, while the aftermarket did not move fast at all
3. Need to get 10,000 weight oil from Toyota and refill new fan clutch, or buy better aqua green one that is used in the fj80 and t100
4. Inspect HAI/HIC system for correct operation of flapper when hot.

 

[FJ Silver]

Ah sh*t... Very curious about how a different weight will work. Good luck

 

[Infinity00]

I burped the radiator again, and no bubbles appeared (on a grade, heaters full blast after getting fully up to temp). I pulled the temp sender, expecting an air pocket but it was filled with coolant. I’ve plugged my HAI vacuum line. I’ll have to run it again up the 1000’ elevation to see if it’ll overheat to determine if it’s the fan clutch. Only problem is the temperature here has dropped by 30 degrees, so if it overheats when it’s this cool I’ll really have a problem. It’ll get hot again next week... anyway here are a few pictures

 

[Infinity00]

Temp sender: does anyone know what the 23 stands for?

 

[brian]

ive been through two of the red hub aisins in nearly as many years...both quit locking when required, actually i dont think the second ever locked up...beening a running a black hubbed not sure of the name clutch that is failed in the perma locked condition. it at least allows me to drive it over the summer....the other two wouldn't permit that.
presently awaiting arrival of one of those green hubbed 3fe clutches.

 

[Infinity00]

Where’d you buy your green hub one? I think I’ll end up going that route as well. Hoping Toyota overstock will take their lame red hub back and refund me my $$.

I did just take it out for a test ride and it stayed cool but the real test will be when it’s mid-90s again.