Toadyota

Finally joined this site! Had my 85 4runner for 10years now, guess it's about time to poke my head in the door.
So I put a 3 row radiator in my truck thinking it would help with cooling since I spend time in the desert. I noticed that I haven't heard my clutch fan working(roaring) lately. After reading about clutch fans I'm wondering if the bigger radiator cools the air too much to make the clutch work. Though my water temp gets up to about 210. The truck has 398,000 on it, rebuilt at 235,000 but same fan.
Any ideas? I'm about to drive through Death Valley and want to address this.

4Crawler

iTrader: (3)

The radiator does not cool the air, it heats it up, transferring heat from the (hotter) coolant to the cooler air, increasing the temperature of the air as it passes through the radiator fins. Might be your fan clutch is no longer operating smoothly. It works via a bimetal spring that turns a shaft in the center to increase and decrease the drag in the clutch. Not uncommon for that shaft to get stuck enough that the spring can't turn it. I took my '85 fan clutch off and used a pair of pliers to grip the shaft and gently turn it back and forth to free it up. Might also be the silicone fluid in the clutch has leaked out:
- http://www.4crawler.com/4x4/Docs/FanClutch.pdf

Toadyota

Hi 4Crawler, been lookin at your site for a long time! I've spent time up in the Black Rock and Northern deserts too, I'll have to see your rig in person someday!
I'll check the fan tomorrow since I have the radiator out getting repaired.
I was just worried about the fan since the water temp seems to get so high, but I'm really not sure what toooo high is? 215, 220, 250? the bigger radiator seems to keep it cool most of the time and I have the higher 190 thermostat so I guess I might be worrying about nothing.

myyota

Man, its nice to see someone in my neck of the woods, im in san pablo on el portal drive, were in el sobrante are you ?, and what have you done to your 4Runner so far ?. As for the radiator, the 3 core is fine, i have a new 3 core in my 4Runner and it works great, so your fan clutch might be bad. let me know if you need any help, im not a pro by any means but i can usually figure things out.

Larry.

Toadyota

You can check out my profile for my upgrades to the truck, I just added them last night. Do you really have 14'' of lift? that's huge! I don't do any real rock crawling mostly just desert trips. It's been a long slow build.
As for the fan clutch-
I know it's not honey but sure looks and feels like it! I think it's the original clutch with almost 400,000 miles on it. So I'm gonna replace the oil and see how it goes from there. Otherwise the inside looks like it just came from the factory!

technojunkie

I'm not sure if I read it here or elsewhere, but there is a test you can do to see if your clutch is engaging properly. Take a piece of thread, and loop it around one of the fan blades, then attach the other end somewhere in the compartment so the thread keeps the blade from spinning. Then start your tuck and let it warm up. If the clutch engages it will snap the thread. If the truck gets warm and the thread is still there; bad clutch.

myyota

Yea, i really do have 14'' of lift, we had a stock 4Runner parked next to mine and we measured the diference, and thats with out the bilstien shocks put on, and they will add a little more lift. I also just realised that i left a few things out of my signature, I also have a solid axle swap, downey header, optima battery, and probably a few other things i can`t think of right now. All i need to finish it is drive shafts, brakes, and exhaust, and it will be done.

Toadyota

You should post a pic of your truck. I'll taking some pics of mine next month when I get to in Death Valley and post them.
For my fan clutch I found that the rod attached to the outside spring appeared to be stuck a little so hopefully that was my problem.
We'll find out this weekend when I the thing back together.
Cheers-

myyota

I need to take some pictures of my truck, and then try and figure out how to post them.