Fan exploded.
03-05-2012, 06:56 PM
#21
Registered User
my .02:
the metal hoop bracket that is riveted to the plastic fan is made of brittle material.
There are 4 nuts holding the metal bracket (and thus the fan) to the hub.
Those nuts like to vibrate loose, providing slop room for the fan to wobble.
The wobble can cause failure of the metal hoop bracket.
This likely occurs at a moment of high engine speed (ie just before a shift point). The fan is spinning at high rpms when the bracket lets go. The bracket and the fan then sort of shatter and scatter.
To avoid this scenario, check your fan with the engine off. Roll it by hand at 45? increments, trying to wiggle it at each point. If it's got a wiggle, you should remove it and inspect the bracket for cracks.
When re-installing, load the 4 little hub bolts with threadlocker. If the nuts never back off from engine vibe, the fan will never get stressed and start failing.
If your fan seems perfectly smooth, remove the nuts and threadlock 'em anyway.
the metal hoop bracket that is riveted to the plastic fan is made of brittle material.
There are 4 nuts holding the metal bracket (and thus the fan) to the hub.
Those nuts like to vibrate loose, providing slop room for the fan to wobble.
The wobble can cause failure of the metal hoop bracket.
This likely occurs at a moment of high engine speed (ie just before a shift point). The fan is spinning at high rpms when the bracket lets go. The bracket and the fan then sort of shatter and scatter.
To avoid this scenario, check your fan with the engine off. Roll it by hand at 45? increments, trying to wiggle it at each point. If it's got a wiggle, you should remove it and inspect the bracket for cracks.
When re-installing, load the 4 little hub bolts with threadlocker. If the nuts never back off from engine vibe, the fan will never get stressed and start failing.
If your fan seems perfectly smooth, remove the nuts and threadlock 'em anyway.
I heard a funny noise coming from under the hood yesterday when my lady and I were going to go up to a state park for some late winter hiking. I heard it from outside the vehicle, and we decided to take her car instead of mine. When I shut off the ignition, i heard the noise continue for 10 seconds and looked under the hood in time to see that it was the wobbly fan.
I wiggled the fan around, and it had a lot of play. I checked the 4 bolts fastening it to the fan clutch - tight as could be. I was confused. So I took the above posters advice, and when I got the fan bolts off, some pieces of metal started clanking through the engine compartment and landing on the ground. See below:
http://www.flickr.com/photos/39633318@N06/6811774488/
The metal is definitely brittle! It lasted 227K miles, so its not that bad, but it seems like cheap metal.
So I went down to Yotayard thinking I could get a used fan, but they wont sell used fans. I bought a new fan for ~80 and installed it and used threadlock. Now things are good.
http://www.flickr.com/photos/39633318@N06/6957884977/
Also, it is clear that the fans should not be re-used, so you should expect to buy a new one. I didnt have time to shop around so I dont know how cheap they can be.
Cheers, and thanks Yotatech! I got to remove a radiator for the first time. (Note: if you do this, remove the radiator before removing the fan & shroud. It's a pain to get the radiator out if the fan and shroud are loose.)
Last edited by California; 03-05-2012 at 07:04 PM.
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