Fan Exploded, is this common?

[giro]

Yesterday I was a little late to head home, and when I jumped in my 92 v6 4runner I took off, gunning it more than I normally do. In first at about 4k rpm, something exploded and there were dents on my hood. I stopped right away, fearing the worst of a thrown rod.

Instead, the fan had exploded, sending plastic shrapnel everywhere. It also took out the fan shroud and the resonator (part of the air cleaner assembly), and later I found it kinked the return metal line for the power steering. And it looks like it took out the upper radiator hose.

The 4runner was relatively warm (drove up the hill an hour earlier), and it was above freezing out. While the 4runner is over 22 years old now, it's only at 159k, and spent most of it's life in cushy conditions (CA, mostly garaged, very little offroading).

What I'm wondering is was this just the end of the life for the plastic fan. Are others this age going to blow soon (i.e. should I stay away from picking up one from Pick-n-pull from a similarly aged 4runner that most likely had a rougher life)? It's not that much to buy one from rock auto, about $50 instead of $11 for the used part. That sounded like a lot at first, but compared to the ~$150 someone quoted previously from toyota it's not bad at all.

I'm also curious about the resonator, which someone else called the "resonance chamber". It's just 2 tubes going into basically a plastic box, and it's after the filter. I'm guessing it just dampens the pressure a bit, and that things wouldn't be too bad if I just bypassed it by connecting the hoses. Does anyone know what it does, or have already bypassed it?

Thanks!
(pics in a followup if I can find a place to host them)

http://www.toyota-4runner.org/classic-t4rs/16977-little-black-box.html
An electric fan would likely work for me, but not worth the time right now http://www.toyota-4runner.org/4th-gen-t4rs/113933-new-fan-clutch-fan-electric-fan-mod-3.html

 

[crazy gringo]

spend the fifty bucks !!!

 

[77'911]

You need to find out if anything seized along the belt route for the fan, otherwise probably collapsed motor and trans mounts. If the mounts are really bad, you hit the gas hard, the fan can hit the shroud. This is a common issue with BMW's.
Those fans otherwise, are pretty robust.
regards

 

[giro]

I'd only gone maybe 100' when the fan blew. After shutting it down and taking a look, I backed up to the house in neutral (downhill) and cleaned out what I could with a shopvac.

After that, I went ahead and fired it up, and things were doing ok. It was nearly all downhill where I needed to go (dropping from 7500' to 6700'), so I went ahead and drove it home.

In checking now, the belt closest to the engine was off by one grove. If this was like that when the fan blew, that could have put a bit of force in the wrong direction, causing the fan to be off from where it should be. Normally, how close is the fan to the shroud?

Looks like the fan also took out the radiator drain cock. At least it didn't take out the battery like it has for some people…..there's marks on the battery, and it took out part of the battery tray, but the battery is intact.

I was able to straighten the power steering return line a little, replace the upper radiator hose with a working spare, and connect the 2 air hoses that would normally connect in the resonator with some 5/8" drip line. In these temps I probably could drive without a fan if I needed to and kept an eye on the gauges. I was going to wait to have that drain plug and replace the thermostat (been needing to do that for a while) to top off the antifreeze, but maybe I'll just do a flush and replace that thermostat now before it snows.

 

[RiFF RaFF]

I'd only gone maybe 100' when the fan blew. After shutting it down and taking a look, I backed up to the house in neutral (downhill) and cleaned out what I could with a shopvac.

After that, I went ahead and fired it up, and things were doing ok. It was nearly all downhill where I needed to go (dropping from 7500' to 6700'), so I went ahead and drove it home.

In checking now, the belt closest to the engine was off by one grove. If this was like that when the fan blew, that could have put a bit of force in the wrong direction, causing the fan to be off from where it should be. Normally, how close is the fan to the shroud?

Looks like the fan also took out the radiator drain cock. At least it didn't take out the battery like it has for some people…..there's marks on the battery, and it took out part of the battery tray, but the battery is intact.

I was able to straighten the power steering return line a little, replace the upper radiator hose with a working spare, and connect the 2 air hoses that would normally connect in the resonator with some 5/8" drip line. In these temps I probably could drive without a fan if I needed to and kept an eye on the gauges. I was going to wait to have that drain plug and replace the thermostat (been needing to do that for a while) to top off the antifreeze, but maybe I'll just do a flush and replace that thermostat now before it snows.

Not sure what happened to yours, but I can tell you what almost caused a catastrophic radiator fan failure in mine.

During some maintenance I notice the radiator fan was wobbling. Removed it, and found 3 of the places where you bolt it to the clutch were broken off. Only one was holding it on. Not good!

I believe the failure was caused when I tried to play submarine captain, and had water deep enough to cause the fan to fail.

Ended up having to replace the fan, clutch, and radiator.

Lessons learned -- if you are forging deep water switch to an electric radiator fan with an on-off switch inside the cab.

OR

Stay out of deep water!

Another thing that can cause a plastic fan to fail is deep snow getting stuck up and under the hood.

 

[4runnerBrett]

Yep I had a broken shroud and my wife's dad pulled the throttle cable and the fan sucked the shroud in and a piece of the fan flew by my face. Was pretty scary.

 

[KidVermicious]

Lessons learned -- if you are forging deep water switch to an electric radiator fan with an on-off switch inside the cab.

Meh, just take a couple seconds to pull the fan belt before you go through. I have yet to be convinced that the electric fan motor is any improvement over the stock clutch.

 

[zeak]

Meh, just take a couple seconds to pull the fan belt before you go through. I have yet to be convinced that the electric fan motor is any improvement over the stock clutch.

I've been running the electric fan for a few months now. If you run the stock fan and then swap to the electric fan, you will notice the deference.
Think about the stock fan like a small airplane propeller. Each time you step on the gas, it creates drag on the crank. It's also a nifty way to stop your belts from screeching.

 

[KidVermicious]

I've been running the electric fan for a few months now. If you run the stock fan and then swap to the electric fan, you will notice the deference.
Think about the stock fan like a small airplane propeller. Each time you step on the gas, it creates drag on the crank. It's also a nifty way to stop your belts from screeching.

Yeah, but on the flip side you've got the additional loss in the electric circuit. And feel is subjective - for everybody who loves theirs, there's just as many that say they couldn't feel a difference at all.

I don't know any numbers, but I'm just not convinced that there's any measurable benefit to going electric, and it's one more point of failure in a critical system.

 

[RiFF RaFF]

Meh, just take a couple seconds to pull the fan belt before you go through. I have yet to be convinced that the electric fan motor is any improvement over the stock clutch.

Kid I respect your opinion, but the 'puddle' I fell into was a LOT (and I mean a lot) deeper than I had expected.

My best advice - stay out of deep water, and probe unknown water holes carefully before advancing.

I do like your advice that if you have to travel through some deep water to remove the belt first.

eace: