Aisin Blue Fan Clutch Product Development

[Trollhole]

Here is your chance to finally have a say about a product. The Aisin Product Development team has contacted me about this issue. I'm not the expert on the issues. But I have the contact with the group. So what I need from you is a background on the issues with OEM part #'s. Any relevant information or ideas you have that could help in fixing the issue. I will in turn relay the information and questions from them to us. Just goes to show Aisin is committed to helping the people that use their parts.

1. History of the issues

2. OEM part #'s in question

3. Current fixes

4. Possible cures

 

[landtank]

I wrote a whole thread on this part. My brand new Blue hubbed clutch did not work once the weather warmed up. I installed it in the fall and as sson as summer hit the engine over heated.

What I eventually found to be the initial problem is that the timing was set at too low a temp and the clutch never started to move enough air for it to effect the bi-metal spring.

So I adjusted the inner plate to react to cooler temps and then also upped the CST of the oil to 5000.

Those two changes have cured my hot running issues for two years now.

I've also have modified a bunch of brand new clutches for forum members and using my crude evaluation technique can say that the temp timing varies widely from clutch to clutch and in my opinion is the biggest problem.

 

[Buckru]

While I didn't adjust the inner plate, I upgraded the viscosity of the oil from the factory filled 3000cst to 6000cst. Made a world of difference.

Buck

 

[Tools R Us]

I won't try to tell the manufacture how to fix their product, they have more testing equipment/better understanding of how it works. But will say IMHO the blue hub is not powerful enough for some applications. Marginally strong enough for soccer mom service in cooler climates, if the rig is pushed at all, it's underpowered. Here in the desert it's underpowered for even normal daily driving, the A/C and cooling system temps suffer.

I have been running the ambient and fan output air temp sensors for a month or so (highs of 75-90F), previously only done it in the summer 110F+. I don't see the logical model for setting the valve at 95F? Not sure where mine is set, have checked it at 108F, off, 116F on, when hot and being it to highway speed it rapidly drops to 112-113F then more slowly temp where it stabilizes to cruising temp. So guessing that where it's set.

For in town, streetlight to streetlight running the fan output runs 125-160F depending on traffic, ambient, etc, so plenty for the clutch to be on. At highway cruise speeds the airflow seams to be well designed, it will drop and stabilize in the 98-106F range depending on ambient, on my rig the fan is off. At 85F it's ~106F and stays there as long as speed (~65mph) is maintained. IMHO having the clutch on under those conditions would only waste energy. This is from in town highway running, will be wheeling over the holiday, so will have some real highway, longer cruise observations after the weekend.

Maybe the best option would be to have a heavy duty option clutch, like the Tacoma has? Most Taco owners here, ether run the "towing" clutch or just change the fluid to 10K.

 

[MyCrush]

Any more activity on this thread from the mfr's ?

 

[Tapage]

does anyone take the oil or water temp on their engines just to verify the fan clutch options ..

 

[jvazquez53]

Didn't even knew there was a blue Aisin fan clutch. My new one has a green hub.

 

[TX Cruiser]

As it should. The green hub has a shorter snout, and is designed for the 3FE. It too responds well to modifications and fluid changes. However, it might not be as effective when put on an FZJ, but it can be done.

 

[jvazquez53]

As it should. The green hub has a shorter snout, and is designed for the 3FE. It too responds well to modifications and fluid changes. However, it might not be as effective when put on an FZJ, but it can be done.

Ok got it clear. I thought that there was one better than the other.

 

[TX Cruiser]

From what I understand, there is. The green one is the best (IMHO), the black one is next and the others merely draw air. Amounts vary dramatically.

 

[informationjunky]

don't know it there is any differance in the LX, can't imagine there is, but my gauge has never gone above 1/2 even when my rad was lid was cracked. This is in the nice coool Georgia summers. My fan clutch is the original w/ close to 180k

 

[80t0ylc]

don't know it there is any differance in the LX, can't imagine there is, but my gauge has never gone above 1/2 even when my rad was lid was cracked. This is in the nice coool Georgia summers. My fan clutch is the original w/ close to 180k

That's cool, but are you being lied to by your stock "center bias" temp gauge or have you done RT's temp gauge mod? You do want an accurate reading, right?