How to service your tired FZJ80 fan clutch.
Tools that are required for the job.
12mm wrench. I used a 12 point but read that a 6 point will reduce your chances of rounding the nuts.
Vice Grips. These are for when you round the nuts.
10 and 12mm ratchet sockets.
T25 star driver.
Can of man.
The first thing that you will want to do when attacking this job is to let the engine cool. If you are impatient, like me you will burn your arms on the valve cover.
Second you will need to take off the 4 nuts that hold the fan clutch on. Using two 12mm would be the easiest, I used a wrench and vice grips. On this step I managed to round off two of the 4 nuts, which complicated my life, but I got over it. I used my can of man and vice grips and got the buggers off.
Third you will need to take out the top two bolts on the fan shroud, I think mine is aftermarket, so you may have more or less bolts than I did.
Next you will take the assembly out, and unbolt the fan from the clutch.
This is after it was already out
Here I used the T25 star driver and pulled the 4 bolts out that are holding the two halves together.
Once the bolts are out you have to pull hard on the two pieces and they will come apart. From here you set one half one something and let it drain overnight.
In the morning you will refill with CST fluid. I purchased a 15k viscosity, I can't remember who told me to get that but I have seen recommendations for 10 and 15k. It can be purchased from your local hobby shop, it's RC diff fluid. I put 30ml back in, Cleaned the fan and put everything back together. It now pushes much more air through than it did previously. I will be getting an ultraguage to get some actual engine temps.
It really is a very simple job, easier than the dizzy o-ring in my book. Just make sure that you have the time to drain it and fill it properly.
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