DIY - Fan Clutch Refill/Rebuild Procedure.. (1 Viewer)

abuck99

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The fan clutch mod won’t improve city/hwy operating temps- it’s mainly for trail use to keep fan engaged at slow speed- lower rpm’s-moves more air and helps with coolant and trans temps
 
Joined
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The fan clutch mod won’t improve city/hwy operating temps- it’s mainly for trail use to keep fan engaged at slow speed- lower rpm’s-moves more air and helps with coolant and trans temps
I’m primarily concerned with asphalt temperatures on heavy LA rush hour traffic (possibility 0-30MPH at times) on the fwy with mufflers / tailpipe pointed towards engine radiators and cars sitting next to each other although I try to avoid getting caught in these conditions.
 
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I’m primarily concerned with asphalt temperatures on heavy LA rush hour traffic (possibility 0-30MPH at times) on the fwy with mufflers / tailpipe pointed towards engine radiators and cars sitting next to each other although I try to avoid getting caught in these conditions.
Anecdotally, I had an LX470 and 100 series in LA rush hour for 8 years and never had heat issues related to the fan clutch.

I'm in TX now (humid and much higher heat index) and just did this mod to give it a try to battle heat problems but I had more success for daily driving and getting lower coolant temp by focusing on other parts of the system (replacing radiator, broken shroud, etc).

If you decide to do this, here's what I did recently (one more data point).

I followed the 80 series directions posted above and adjusted the screws to open at a diff temperature. I also started with a new Aisn 'Blue Clutch' FCT-021 and drained existing oil (took about two days) which was a lot less than what I put in, and filled with approx 45ml of 20k CST.

I can idle with AC on max on a hot day in direct sun (107* and super humid) and not go past 194* coolant temp) BUT I really can't tell you if that's the result of the fan clutch. In my case, all other cooling components are brand new with toyota red. Also, in my case I've had a noticeable drop in engine power (by feel, no actual readings taken).

If I were in your shoes in LA I'd focus on other parts of the cooling system first but if you're determined to do this mod for daily driving I would start with a new blue hub Aisn, drain it, adjust the opening timing, and fill with approx 40ml of 15k.

Be aware the viscosity and quantity of oil change based on the type of fan clutch you're using, supposedly your target/ambient temperature, and how much HP you want to give up. Everything around this mod seems to be "he said she said and this worked for my cousin...". YMMV!

For anyone else following, if you want to try and mix oils to get a specific viscosity this calculator may help:
 

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