Genuinely do not understand how this happened. (Fan and Fan Clutch)

[Lost Steez]

To give a synopsis, I have owned this LC for a month now. I recently made a trip down into the Goldwater range, driving roughly 20-30 miles on washboard roads. Drove another 50 at highway speeds home. A couple hours later, I start it up, start driving and hear a grinding/clanking sound. Pulled over thought maybe I did something to the suspension/steering, was looking underneath and notice my fan and all four bolts laying on the fan shroud completely detached. Tried putting it back on, at first nothing was working becuase some of the bolts were bent from hitting the fan clutch and after i got them in, I couldnt seat any of the threads. Eventually I got it on and tightened. But I have no idea how this could happen, what it may indictate and if i need to balance the fan/clutch.

TL/DR: Drove offroad then 50 miles home on the highway. Started the car later and fan + bolts fell of the fan clutch. How did this happen?

 

[excessive]

never seen that failure before! I wonder if that is the OEM Fan clutch? the OEM is known to last a very long time. at least it didnt take out your radiator?

 

[2001LC]

Likely some cheap china junk fan clutch.
OEM fan clutch has stud coming out front, nuts go on fan side and once torqued in, sit nearly flush with stud.

Aisin one shelve below in build standard, then that of Toyota Aisin (top shelve). They look & fit just the same as OEM. Thicker one is for 06-07 VVTi 4.7L

 

[3_puppies]

more failure analysis needed
are the nuts tight between the fan and studs?
the studs shouldn't be able to rotate loose if those are tight
is there threads left in the housing for the studs?
did it damage the rad?

 

[OEMGUY0720]

Wow the flange actually separated from the clutch assembly but the failure was at the opposite end of the stud where it is fastened to the clutch unit.

 

[Lost Steez]

never seen that failure before! I wonder if that is the OEM Fan clutch? the OEM is known to last a very long time. at least it didnt take out your radiator?

Definitely! Only a couple dings but no major damage. I can’t get a good look at it, but it looks like the oem AISIN one, my best guess is installation error from the previous owner.

 

[Lost Steez]

more failure analysis needed
are the nuts tight between the fan and studs?
the studs shouldn't be able to rotate loose if those are tight
is there threads left in the housing for the studs?
did it damage the rad?

Yep, all tight, was flush when put back on by myself. Drove one more time this week and checked often. Unfortunately, it backed itself out again and is causing a minor leak to the radiator. Probably stripped, but they all seem to seat and sit flush.

EDIT: Here are some photos after I put it back on before it fell off most recently. All tight, some had slight gaps, but it didn't wobble when running. Some bolts were slightly bent they were a pain to get on, but I got them in, and maybe they held the fan in despite the housings being stripped. Regadless I'll post an update once I tear everything out.

 

[hoser]

The OE studs cannot unscrew out like that. Only buy Aisin parts from reputable seller or dealer.

 

[3_puppies]

wonder if there were nuts on the backside of the studs and not threaded into the housing???

 

[GTV]

It’s either junk parts and/or bad installation. Hopefully you’ve eliminated the latter. If it was mine I’d replace the clutch with a genuine part and possibly the fan as well.

 

[scubadoober]

You put it back together, and ran it after this?! Learning can be the price of a radiator sometimes.

 

[excessive]

has anyone ever heard of a fan failure? Back in my BMW days it was common for fan blades to just come off and be sent through the hoses/ radiator. I've never heard of that failure on a Toyota, but who knows with the age of these things now....

 

[Lost Steez]

Just placed an order from Olathe, doing a bunch of stuff while I'm in there. After pulling out the clutch today Ive found that all four housings for the bolts are completely stripped. The clutch itself looks to be original but has no Aisin branding, dont know if Toyota OEs looked like this or if it's aftermarket, I would guess the latter. Also, there was a set of washer nuts that are not in the FSM or partsouq, leading me to believe this is not OE/OEM and had some sort of installation error from the previous owner.

 

[Lost Steez]

The top nut/washer combo shouldn't be there, the fan should sit flush to the clutch (as @2001LC mentioned), and the bottom bolt should secure the fan to the clutch.

 

[Lost Steez]

You put it back together, and ran it after this?! Learning can be the price of a radiator sometimes.

Yep. Lulled myself after it went on and was not coming off with force or after driving for a week. Definitely an expensive lesson, and completely stupid decison but a bunch of cooling system parts are original at 227k, and this was a good push for me to baseline it.

 

[GTV]

has anyone ever heard of a fan failure? Back in my BMW days it was common for fan blades to just come off and be sent through the hoses/ radiator. I've never heard of that failure on a Toyota, but who knows with the age of these things now....

When I got my Tundra it had 3 broken/missing blades but no evidence of collateral damage.