Early 1FZ Fan Clutch (Black/Blue Hub)

[arndog123]

10K works great on both my 80's here up in WA. They're adjusted using LT's method too.

 

[80t0ylc]

10K works great on both my 80's here up in WA. They're adjusted using LT's method too.

Thanks, arndog! I won't get to it until tonight at the earliest. It irks me that our only choice for a new part is this clutch, that is not recommended to be modified. And yet is factory tuned to be wimpy.

 

[Tools R Us]

week performance...
fixed it

Good one! Yep, they have performance for weeks. If you are referring to weak, I doubt any who have would use that term to describe them.

The way we set them up is the result of tons of experimentation to find the best/most powerful setup. Have set the valves all over the place, used/tested fluids all the way to 30K. Some have been apart so many times that the joke is; they should be put together with Velcro to make it easier. A lot has been learned, but are continuing to learn, so what was known/done years ago is obsolete.

If the valve is studied, there are basically 3 steps/zones. On some the center step is progressive, but still 3 steps. If a study is done of fan output temps, combined with coolant, A/C vent, etc, temps, there are also 3 heat zones of fan need. Those heat zones match very well to the temp steps at the stock setting, maybe the engineers aren’t as stupid as some thing they are?

Below ~120-130F of fan output temp there is zero need for fan. This time of year (~70-80F for the high) they will cruise at 60-75mph ish with a fan output temp in the 100-120F range/coolant 190F ish all day and this is with the clutch set to come on at 125F ish, so no fan assist. As more load is added, hill, A/C switched on, etc, slight assist is needed, this is the first step. Even more load, big highway climb, slow traffic, wheeling, towing, etc, progressively more assist is needed, this is the second step, often progressive. When stopped, idling, especially in hot weather, with A/C, etc, is by far the highest fan output heat load, can be 170-200F fan output, this is the third step. It is the biggest and most powerful.

When the valve is cheated down say 30F, it will work and be stronger than stock, but without some of the benefits of the stock design. Basically each step is moved down one. The first step is wasted, blowing air around when not needed, wasting energy, putting unneeded wear, etc. The second step is used for lightly loaded cruising. The third step (full open, very strong) is used for heavy loaded cruising, big highway climb, slow traffic, wheeling, towing, etc, works strong for this. Now stop let it idle, hot, A/C on, etc, still on the third step/wide open, no additional assist at the time when it is needed most.

We have found it to be beneficial to leave the valve alone, it matches well with temp need and heavier on the viscosity. This makes each step stronger, doesn't waste energy/power blowing air when not needed and most importantly is very strong at idle, reducing the chance of A/C cutoff, cooler A/C vent temps at idle and recovers quicker from heat soak. This is the strongest, best all around performing setup we have found.

 

[Tools R Us]

Thanks, arndog! I won't get to it until tonight at the earliest. It irks me that our only choice for a new part is this clutch, that is not recommended to be modified. And yet is factory tuned to be wimpy.

The new blue hub is a good clutch, when compared to other brands, a great clutch. It is very nicely made, durable, unfortunately the shearing area is reduced, so is normally weaker than the earlier clutches with the same fluid. This can be mostly overcome by going to a thicker fluid, for most they work great. Our testing/experience is; they require over twice the viscosity to have the same performance as the earlier clutches.

 

[95ToyCruiser]

I have a 95, but I'm pretty sure (from memory 6 months ago) it was a black hub? whatever the color of it may be, I will be doing a fluid change on it.

Where do you get the fluid? Toyota? Do they stock fluid up to say 15k?

Thanks,

Shane

 

[80t0ylc]

Good one! Yep, they have performance for weeks. If you are referring to weak, I doubt any who have would use that term to describe them.

The way we set them up is the result of tons of experimentation to find the best/most powerful setup. Have set the valves all over the place, used/tested fluids all the way to 30K. Some have been apart so many times that the joke is; they should be put together with Velcro to make it easier. A lot has been learned, but are continuing to learn, so what was known/done years ago is obsolete.

If the valve is studied, there are basically 3 steps/zones. On some the center step is progressive, but still 3 steps. If a study is done of fan output temps, combined with coolant, A/C vent, etc, temps, there are also 3 heat zones of fan need. Those heat zones match very well to the temp steps at the stock setting, maybe the engineers aren’t as stupid as some thing they are?

Below ~120-130F of fan output temp there is zero need for fan. This time of year (~70-80F for the high) they will cruise at 60-75mph ish with a fan output temp in the 100-120F range/coolant 190F ish all day and this is with the clutch set to come on at 125F ish, so no fan assist. As more load is added, hill, A/C switched on, etc, slight assist is needed, this is the first step. Even more load, big highway climb, slow traffic, wheeling, towing, etc, progressively more assist is needed, this is the second step, often progressive. When stopped, idling, especially in hot weather, with A/C, etc, is by far the highest fan output heat load, can be 170-200F fan output, this is the third step. It is the biggest and most powerful.

When the valve is cheated down say 30F, it will work and be stronger than stock, but without some of the benefits of the stock design. Basically each step is moved down one. The first step is wasted, blowing air around when not needed, wasting energy, putting unneeded wear, etc. The second step is used for lightly loaded cruising. The third step (full open, very strong) is used for heavy loaded cruising, big highway climb, slow traffic, wheeling, towing, etc, works strong for this. Now stop let it idle, hot, A/C on, etc, still on the third step/wide open, no additional assist at the time when it is needed most.

We have found it to be beneficial to leave the valve alone, it matches well with temp need and heavier on the viscosity. This makes each step stronger, doesn't waste energy/power blowing air when not needed and most importantly is very strong at idle, reducing the chance of A/C cutoff, cooler A/C vent temps at idle and recovers quicker from heat soak. This is the strongest, best all around performing setup we have found.

Ok, Kevin. I'm convinced. It's been draining for 2 days. I'm just going to put 45-50 ml of the 10K cst in and button it up. I flirted with adjusting it, but I can still do that later and/or put in heavier fluid, if needed. Thanks again!

Edit: I cant wait till this week end to be able to tear into the OEM to see what made it fail. I'll keep you posted.

 

[80t0ylc]

........... It irks me that our only choice for a new part is this clutch, that is not recommended to be modified. And yet is factory tuned to be wimpy.

The new blue hub is a good clutch, when compared to other brands, a great clutch. It is very nicely made, durable, unfortunately the shearing area is reduced, so is normally weaker than the earlier clutches with the same fluid. This can be mostly overcome by going to a thicker fluid, for most they work great. Our testing/experience is; they require over twice the viscosity to have the same performance as the earlier clutches.

My comment was directed at the wimpy fluid that comes stock, with no choice (with out the not recommended modification). I agree that is very nicely made. I hope the bearing holds up like the OEM (230K miles).

 

[80t0ylc]

New clutch in and works like a charm. The OEM is not so great. In fact it's garbage. The bearing is toast and the nice new 10K fluid put in 7 months ago looks terrible. It's the color of graphite. Well, if I've learned anything, it would have to be this: If you open up a clutch to upgrade the fluid and you have black dots or specs in the original fluid, chances are you will soon be replacing that clutch. The outside looks fine, spring's in good shape, so I don't think environment did it in. It might be the age and use - 230K+ miles, which in reality is above average. For those interested, a couple of pics of inside of the OEM (black hubbed Aisin):

 

[Tools R Us]

New clutch in and works like a charm. The OEM is not so great. In fact it's garbage. The bearing is toast and the nice new 10K fluid put in 7 months ago looks terrible. It's the color of graphite. Well, if I've learned anything, it would have to be this: If you open up a clutch to upgrade the fluid and you have black dots or specs in the original fluid, chances are you will soon be replacing that clutch. The outside looks fine, spring's in good shape, so I don't think environment did it in. It might be the age and use - 230K+ miles, which in reality is above average. For those interested, a couple of pics of inside of the OEM (black hubbed Aisin):

The graphite colored stuff is alloy from the parts rubbing together. The tolerances are very close, when the bearing goes, the parts touch/rub. The bearings/whole units are very durable, but the rare failure happens. I know of a couple that are still going strong at 300K+ miles. Killer life, most other types of clutches are lucky to go 50K miles.

 

[coax]

Bumping an old but good thread

I had the opportunity to pick up a used black hub, unknown condition. One of the screws had stripped when putting new fluid in to the original eaton, so had been wanting to swap clutches for a while. It was pretty dirty with probably 20 years of gunk on it, but it cleaned up ok. The fluid was quite clear inside as well.

I didn't see a whole lot of info on setpoints, so I got out the infrared thermometer and took some readings. I tried to measure at the spring or right in the middle. Used a heat gun to open up the sprin and attempted to grab a temp reading. I just left the setpoints where they were. Maybe they'll be useful for reference (with a sample size of 1). Some don't line up exactly as I had to set down the heat gun, grab the camera, etc.

1. 107 - At the beginning of 1st stage I guess.
2. 124 - 1st stage fully open.
3. 142 - Small "notch" start.
4. 158 - Small notch open fully.
5. 170 - 3rd stage starts. (#'s 4 and 5 should probably be the same reading.
6. 190+ - 3rd stage all the way open.

Anyone have any thoughts on these readings? They seem to line up reasonably well with Tools post #63 above? I haven't had the chance to put it back in the truck. Filled with about 40ml of 10k fluid, I didn't wait too long for every last drop to drain out before filling again.

 

[DSRTRDR]

I didn't even test ours, I just put the 10K into the black hub clutch

 

[mandinga]

Anyone recommend where to buy the 10k fluid?

 

[coax]

I got mine here:
http://www.amazon.com/gp/product/B000SLOW7I/ref=oh_details_o06_s02_i00?ie=UTF8&psc=1

 

[mandinga]

Ordered.
Thanks for the speedy reply.

 

[Michael Hanson]

Ok it had to happen sooner or latter ( 330,000 miles ) our fan clutch died or at least the oil did taking my son an OEM set of springs in the Ozark Mts. for the fj62 . Rick I'm going to replace the oil with 10,000 and not reset the thermostat based on what I read from your many great posts, does that sound right ? Thanks, Mike

 

[80t0ylc]

Ok it had to happen sooner or latter ( 330,000 miles ) our fan clutch died or at least the oil did taking my son an OEM set of springs in the Ozark Mts. for the fj62 . Rick I'm going to replace the oil with 10,000 and not reset the thermostat based on what I read from your many great posts, does that sound right ? Thanks, Mike

Mike, since Rick hasn't responded yet - by saying your fan clutch died, you mean locked up, right? (can't spin fan blades by hand with engine off) If so, you need a new fan clutch. Replacing oil will do nothing for you because the bearing has seized. If you go the route of the new blue hubbed clutch, I'm running approx 25K cst in mine in Oregon. Being as you're in warmer climes in TX, I'd go at least 15 - 20K cst, IMHO. Good luck in whatever you choose

 

[ewillis]

That one is adjustable, but I wouldn't adjust it, upgrade the fluid and enjoy the new found performance.

So @Tools R Us I have one of these puppies. I was going to swap it for a blue hub, but figured I just refresh the fluid in the black hub....trying to capture the spirit of @inkpot Sonoran SuperKooler system

Anyhow...seems 10,000 cst at about 50ml or whatever comes out is still the consensus? Also, this clutch has 122K miles on it and the drag feels pretty tight...IDK if that matters as the oil is still 23 years old. TIA

 

[Tools R Us]

Yep drain it well and replace with ~45ml.

 

[rc51kid]

I filled my older clutch with 45ml. Then went back later and filled it slap full to see if it would cool better. No difference. I would do the 45ml as recommended.

 

[Tools R Us]

I filled my older clutch with 45ml. Then went back later and filled it slap full to see if it would cool better. No difference. I would do the 45ml as recommended.

Overfilling will just make it stay "on" full time, wont change how much torque it can deliver.