My fan clutch does not lock up when my temps reach over 230* :eek: It just free wheels. So I took my 78 2F fan clutch apart yesterday to replace the silicone fluid inside. Anyway, does anyone know the required amount of fluid? I have heard lots of people say it takes 35mL (2 bottles), but my manual says 50mL (3 bottles). Has anyone done this?

Thanks.

Never heard anyone replacing fluid, normally when the fan clutch is shot you throw it away and get a new one.....:skull:

Or drill a hole all the way thru it and insert a bolt with a nut. I am curious of the correct answer though. Good Luck.

Where did you get the fluid? Is it on the same aisle with the muffler bearings and blinker fluid? seriously I am very curious about this as both my cruisers have bad fan clutchs and they are kind of costly to replace so a repair option would be very nice.

Originally posted by SpaceGhost
Or drill a hole all the way thru it and insert a bolt with a nut. I am curious of the correct answer though. Good Luck.

Haven't bought the fluid in ages, but last time I did it was from NAPA. Cheap fix, and usually good for another 5 years! SOME fan clutches will have a nice big screw head. Remove it, insert more fluid, and your set. In reality you should take everything apart, replace the o-rings, and all that good stuff. For a cheap 5 year fix, replacing the fluid is fine 90% of the time. More modern fan clutches are "pitch in the trash can". Sigh.

Problem with putting a bolt through the fan clutch... well the fan stays on all the time. Since the fan is only meant to spin up to 2,500 rpm there is a slight problem. If you are running down the freeway at 4,000 rpm (OK, we don't do that to 2F engines!) the fanbelt may start slipping more than you expect. At freeway speeds the fan isn't needed with all that air passing the radiator, but the other side of that pulley is the water pump impeller. Yes, if the belt slips enough, slows the water pump down... and you start to overheat, even though "Bubba's radiator shop fixed your slipping fan clutch!" :eek:

When everything is cold, that fan should just move freely. After you shut the engine off, and everything is nice and hot, you should feel a good resistance when you try to spin the fan. No, it won't "lock up", but should be able to feel a good drag on it.

Oh the "been there, done that" I once locked up the fan on my Rotary Mazda. On that model it was driven right at the end of the crank shaft (eccentric, but were not that picky). Ahem, during a off road race the fan shed all its blades but one.... and was so out of balance at 8,000 rpm (rotary, don't try that with a 2F) that the gear shift level beat my leg black and blue before I could shut down the engine (about 8" of movement at the end of the shifter!). Screw up enough times, and you learn some neat stuff! :D

Tom :usa:

Tom,
You are certainly right, I should have said that tongue in cheek. On a slow moving trail only rig the effects are minimized. I have an elctronic clutch fan on my powerstroke that disengages the fan completely, or automatically when you depress the accelerator.

Originally posted by SpaceGhost
Tom,
You are certainly right, I should have said that tongue in cheek. On a slow moving trail only rig the effects are minimized. I have an elctronic clutch fan on my powerstroke that disengages the fan completely, or automatically when you depress the accelerator.

Funny part.... I've seen that "fix" done by a "Bubba's auto repair".

Need to look at a powerstroke to see how that fan is coupled. Lots of odd variations, but more common to see all accesories taken off line for maximum passing performance. I.e. full throttle and turn off the A/C clutch & alternator! Helps with those published spec's.... and when I would forget to downshift on my Maxima I would notice the A/C quit working. :eek:

ODD BALL: '92 Nissan 240SX... there is an electric fan behind the radiator, and an ENGINE driven fan too! Usually you see one or the other. All I can figure out is the electric was to help reduce heat soak (let it run after the engine is shut off), but for stop and go city driving not enough cooling? :confused:

Eric -- just where did you buy the silicone clutch fluid? I checkedNAPA (http://www.napaonline.com) but only found major rebuild kits for the fan clutch. No little bottles of fluid. Hmm. I had filled mine up about 2/3rds full. Might explain the "recommended fill" vs. "capacity" numbers.

Tom :usa:

Mine isn't stock it is a Cyclone by US Gear. It bolts to the water pump then the fan mounts to it. Has sensors for temp and throttle position, will come on if the tranny temp gets to 180 or water temp is too high. When engaged it is much better than a fluid coupling, like direct coupling, and make the air conditioner much cooler. The cooling fan is only needed occasionally at any speed on a Stroke, heat is their friend.

I got the silicone liquid from the Toyota dealer. The part number is 08816-03001 for an 18mL bottle of 3000 (something related to viscosity - forgot what they measure that in).

My Toyota manual says to use 35mL of 1000 for all motors, but FJ40/USA says to use 50mL of 3000. My cost with TLCA discount was about $6.50 per bottle. I figure I will give it a shot to see if it works. If not, I will throw in my electric fan or try a junkyard hilux fan clutch.

Originally posted by SpaceGhost
Mine isn't stock it is a Cyclone by US Gear. It bolts to the water pump then the fan mounts to it. Has sensors for temp and throttle position, will come on if the tranny temp gets to 180 or water temp is too high. When engaged it is much better than a fluid coupling, like direct coupling, and make the air conditioner much cooler. The cooling fan is only needed occasionally at any speed on a Stroke, heat is their friend.

Neat stuff. :cool:

On my '02 2500HD... nice addition was a temp gauge for the transmission. No, just a 6.0 gas, 2WD. Still one cool crew cab tow vehicle!

One thing I ran into when working with Ford was the microcontroller for the transmission. They like it built into the tranny, but needed a full operational spec up to 150C! The flash memory is rated for 125C over a ten year life span (no not continous for ten years, but that is another story... ). Idea was when towing up the Rockies you could see 150C (about 300F) for an extended period of time. Yes, the electronics are cooled by the transmission fluid. Hard to do when running HOT! :p Fun part about my old job was playing with all the automotive stuff in development.... Then again the Politics :barf:

Tom :usa: