Mod New Blue Hub Fan Clutch?

[Flank]

What is the volume of the tubes of silicone the Toyota sells? Dan was not sure when I talked to him.

 

[96r50]

I want to say 18ml, but I'm not 100% on that.

 

[Tools R Us]

Correct me if I'm wrong, Kevin, shouldn't he (or anyone for that matter), just be concerned with the hottest temp range that their rig will be exposed to? The fan clutch will just free wheel, or stay in it's lowest step, in the cooler weather, once the fluid gets pumped into the reservoir, until hot enough temps are experienced to engage the clutch.

In theory I agree. My rig has never been in more than relatively minor snow storms, because the owner is a when it comes to cold! So I will leave that testing to someone who knows cold.

 

[Tools R Us]

I want to say 18ml, but I'm not 100% on that.

Agree, all that I have seen are 18ml.

 

[Ebag333]

Correct me if I'm wrong, Kevin, shouldn't he (or anyone for that matter), just be concerned with the hottest temp range that their rig will be exposed to? The fan clutch will just free wheel, or stay in it's lowest step, in the cooler weather, once the fluid gets pumped into the reservoir, until hot enough temps are experienced to engage the clutch.

In theory I agree. My rig has never been in more than relatively minor snow storms, because the owner is a when it comes to cold! So I will leave that testing to someone who knows cold.

While I don't know extreme cold, we do get all four seasons around here.

My thought is that cold will make the fluid thicker. It could make the fluid thick enough that the fan would spin at high/locked speeds more often (or perhaps even all the time). But considering the engine compartment will warm up to 100*+, and the fan clutch should warm up at least close to engine coolant temps, that should only be temporary until the engine warms up. Might wear out the fluid/clutch a bit sooner, but probably not enough to worry about.

 

[96r50]

It gets cold here in the winter. I've yet to run with the 15K fluid in subzero temps, but last winter with 7K fluid in the clutch, the Scangauge was showing 178-183F. I doubt the fan clutch gets much past the first of the three valve opening stages. The start up roar was present and took longer to drop off than in the summer, but it would stop after a minute or so.

Sidenote: last winter my transmission temperature gauge never hit 140F until I made a cover for the auxiliary transmission cooler out of some windproof canvas. With the cover on, I saw ATF temperatures of 149-158F, and the coolant temperature would rise faster after a cold start.

Side-sidenote: These numbers are nicer in Celcius!

 

[Ebag333]

Sidenote: last winter my transmission temperature gauge never hit 140F until I made a cover for the auxiliary transmission cooler out of some windproof canvas. With the cover on, I saw ATF temperatures of 149-158F, and the coolant temperature would rise faster after a cold start.

Pic or it doesn't exist!

Seriously never hit 140*F? What was ambient? How did it affect coolant/engine temps?

I've considered making a grill cover similar to the big rig trucks for winter driving. Now I'm really pondering it....

 

[96r50]

Pic or it doesn't exist!

Seriously never hit 140*F? What was ambient? How did it affect coolant/engine temps?

I've considered making a grill cover similar to the big rig trucks for winter driving. Now I'm really pondering it....

Ambient was anywhere from -15 to +20F.

I have no pics at the moment, but it is simply a couple of layers of heavy Cordura nylon-type material with a windproof layer of nylon (old tent fly) sandwiched in between. It's as wide as the cooler and slightly more than twice as long so I can velcro it in place. I'll try to get some pics of it installed on the spare transmission cooler I have.

Without the cooler cover, if I kept it out of 4th gear and TC lockup (by hitting the O/D off switch) the ATF temps would get up to about 140, but I figured that wasn't a great long term or long distance solution. When the TC locked up, ATF temps never got to 140.

I originally ordered a Derale thermostat (Derale Cooling Products 13011) to install inline, but I didn't like the idea of cutting the lines and I wasn't that impressed with the thermostat itself. The first cover I made only zip-tied to the front of the cooler, and while I noticed a small improvement in ATF temps, it wasn't much. Version 2.0 wraps fully around the cooler and blocks airflow through the front and fan suction at the rear. Since the ATF cooler is spaced away from the condenser and radiator I'm not worried about it blocking airflow to the engine (how much blisteringly cold air does an engine need anyway!)

With the cover installed, ATF temperatures would hit 150-160F by the time I got to work (25-30 mins). In the spring I hit 185 (I took it off that day)

I also made a "winterfront" that was to zip-tie on to the backside of the grille and block airflow through the whole thing, but I didn't go very far with that idea. I'm planning on mounting a second ATF cooler next to the OEM one and using it to increase the power steering system volume and to keep it cool. When I do, I will make a second Version 2.0 cover and between the pair of them, most of the airflow to the rad should be limited.

 

[smokethedog]

If they are true old school black hub Aisin clutches. I would refill with 10K and ~45ml.

what would you recommend for the blue fan clutch?

 

[80t0ylc]

In theory I agree. My rig has never been in more than relatively minor snow storms, because the owner is a when it comes to cold! So I will leave that testing to someone who knows cold.

Yup, I'm that way about heat. I prefer -25*F. I mean at least you can dress for the cold. But, when it breaks the century mark, I've already started to melt. Well I've got the 10K cst fluid and I'm waiting for winter. My '94 won't have a nice snug garage this winter. This part of Oregon (moving to John Day) will see slightly colder temps, than around Bend. About the same elevation, but father from the ocean. I might be tempted to do what Adam & Gabe are talking about for the grill when it gets down to 10*F or below. I had a combo bug screen & winter cover kit for a Ford E150 Van I got through JC Whitney back in the early ninetys. It was a 2 piece kit that snapped to the plastic grill. The winter cover had the ability to be folded open in sections to allow for warm spells. It was made out of black vinyl and had a kind of quilted appearance that actually looked kinda neat, installed. The bug screen piece was, - well, your typical bug screen. The winter cover piece worked quite well. I was living in Wyoming, then, and we could see -30*F nights occasionally.

 

[JerseyCruiser]

Two years ago I modded my blue fan clutch valve and added 6K oil to it, seemed OK got a roar at startup and could hear it kick in when it got hot but not so loud. Last week it hit 103 here and driving around AC on the needle got to about 2 needle lengths from the red. I did Raven's mod with Darwood's 100/150r setup which would show a lower temp on the gauge when hot which I wanted because a 1993 gauge reads a little hotter. What is concerning is that the bottom of with the 100/150 mod would be an overheating issue and would prompt me to shut it off. The engine is in perfect shape 10k (3 years) ago I replaced the HG, radiator, t-stat, water pump, and fan clutch all OEM and flush the system every 2 years. While driving around the AC was cold and never cut out. Even with the gauge mod I have no way to read my actual temp being the truck is OBD1 so no Scangauge. For the mean time I bought a chepo clutch to run until I fix mine, the next day it got to 100 and it roared a lot louder and did not come as close to the red as the day before. That tells me that the clutch is not doing its job. It seems now that I was wrong to change the valve settings according to Tools but not to Landtank, should I switch to 10K oil leave the valve were it is or move it back to stock. Right now I'm good at idle with the AC on that would be the lowest temp, but pushing up a hill with AC on is where it heats up fast even in 50 temps with the AC on it climbs. Sorry for the drawn out post but just need some advice here.

Thanks
George

The CHEAPO ($59.99) Clutch:

 

[Flank]

A lot of information, crosstalk, and etc!!! Now completely convinced that I am more confused than ever. Here is my mode at this point:

receive my blue clutch on order, fill it with the 10K and run with it. Keep old black clutch as a spare, if needed, fill IT with 10K.

 

[96r50]

A lot of information, crosstalk, and etc!!! Now completely convinced that I am more confused than ever. Here is my mode at this point:

receive my blue clutch on order, fill it with the 10K and run with it. Keep old black clutch as a spare, if needed, fill IT with 10K.

If you already have a mechanically sound black clutch I'd keep it and start with that. 10K in it should give you a noticeable increase in cooling power from the fan. If you don't want it, I'll take it off your hands and give it a whirl

 

[Tools R Us]

... I mean at least you can dress for the cold. ...

I also dress for the weather, ~330 days a year the laundry is shorts and tee shirts!

what would you recommend for the blue fan clutch?

A lot of information, crosstalk, and etc!!! Now completely convinced that I am more confused than ever. Here is my mode at this point:

receive my blue clutch on order, fill it with the 10K and run with it. Keep old black clutch as a spare, if needed, fill IT with 10K.

A bunch of setups have been reported to work. I don't know if a universal setup would work best for all, there are too many variables? I suspect that the majority are operated in climates where it's not that important, anything in a relatively large range will work?

Here it's more critical, it's like a couple of my proving ground customers have said: If we can make them run/cool well here, they will work great in the rest of the country, that is why we all have test facilities here.

I see 4 main categories:

1, Old type black/blue hub Aisin clutches. These are the strongest, respond well to viscosity change. All have reported great performance with 10K.

2, Original Eaton clutches. There are slightly weaker, running fluid in the 12.5-15K range is working well in them.

3, New type blue hub Aisin clutches. Our experience is; these are the weakest, have to step up on the viscosity to see results. Most are reporting good results at 20K+. A couple are running 30K, I have not had the chance to travel/wheel with them to compare performance and haven't tried it.

4, Supercharged rigs. Here the fan is most important, the clutch secondary. I have seen very tight clutch equipped rigs, have issues when running the ring fan. The first fan that I have seen work well enough for desert climate is the 3FE fan, the results are early, but looks good.

These are numbers that work here and are subject to change, still playing with them, did two this week. Cold testing is weak, I have only started/run in ~20F and a few relatively minor snow storms. How these numbers would work, if they are necessary/beneficial in other climates, I have no idea.

Good airflow is important, but is only one component of a good cooling system. The clutch is relatively easy/cheap to do, so it's my first check. If it fixes the problem great, if not it's eliminated as a possibility.

Direct comparison between rigs is difficult, there are too many variables, use, heat load, cooling system condition, etc. If your looking for the "best" clutch for your rig, experimentation is your friend. It is relatively easy/cheap to do, so try something, if you feel it could be better, try again. One of the jokes on a couple of rigs is; we should just mount this stuff with velcro, would make it easier! A few rigs have had the clutch off several times attempting to hit the mark.

 

[smokethedog]

I bought a new fan clutch from Dan about 5-6 years ago, the blue one. How do I tell if it is the old type or the new type Aisin clutch???

Its worked fine until last summer. I'm not overheating or even coming close, the factory gauge never moves. But I have a scanguage and see temps vary from 193-20X depending on traffic and speed. I think the engine suffers from heat soak at lower speeds which leads me to believe the FC is getting weak....

I also switched to the 3FE fan at the same time.

Thanks in advance

 

[psfpilot]

Blue is new. Black is old.

Has the stock fluid been replaced with a more viscous version? $15 if purchased online; after reading in this thread that Arizona people are successfully running 20k+ I'm going to replace the 10k cst silicone with 30k to see how it affects my AC duct temp in low speed/low RPM conditions before I try tweaking the clutch thermostat setting.

 

[Ebag333]

I bought a new fan clutch from Dan about 5-6 years ago, the blue one. How do I tell if it is the old type or the new type Aisin clutch???

All blue hubs's are the "new" style. Black hubs can be the old style or an Eaton.

 

[Tools R Us]

All blue hubs's are the "new" style. Black hubs can be the old style or an Eaton.

All black hubs are old type. Blue hub could be old or new type, but the old type is very rare, almost all are new type. All Eaton that I have seen have naked, unpainted hubs, often with a small blue dot.

 

[96r50]

Pic or it doesn't exist!

Seriously never hit 140*F? What was ambient? How did it affect coolant/engine temps?

I've considered making a grill cover similar to the big rig trucks for winter driving. Now I'm really pondering it....

Told you it exists

 

[Flank]

Where are people sourcing 15K, 20K, 30K silicone oil? Does the local Pep Boys, Napa carry it? Toyota only sells up to 10K.