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More alternator troubleshooting.

First off- thanks to all the "pelicans" out there who have helped me thus far. I'm not uh of a mechanic, but with the help of this forum, I'm comfortable tacking some basic procedures.

I had an earlier post with a rattling and bad noise from fan, smoke from center of fan, and fan belt skipping and alternator light on.

I have since taken the fan out and noticed that it spins rather silently. I was expedition bad bearings, but while spinning I heard te noise again....it seems the fan blades are acraping the housing. Almost as though the alternator is loose a little in there and because of it, stalling out on the fan as it scrapes the housing.

This make any sense? And if so, what's the fix?

Old 02-09-2015, 03:18 PM
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Try tightening the alternator mounting nuts counter to where the scraping occurs. This may help.

Check the fan housing blades for cracks. Once the cracks connect, the housing is toast. Do not over tighten the fan belt.
Old 02-09-2015, 03:36 PM
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I just had a similar problem. The fan would sometimes hit the housing. I took it out and discovered that the rear plastic cap had fallen out. It showed me that the rear bearing was bad , lots of play. The cap was keeping it centered sometimes. You need a new alternator. I just installed a Bosch rebuild last night. Works great now.
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Old 02-10-2015, 06:16 AM
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OP, please close out the other thread by updating that you in fact have removed the fan. People are trying to assist you but we depend on you to update your own posts.

Posting pics would help allot too.

I am a bit confused, if you taken the fan out, how did you manage to spin it in the fan housing? Do you mean you spun it before removing it?

Noise you are suspecting is the scrapping of the blades on the housing, then +1 your housing could be cracked and damaged, may need a new fan housing.

If the noise is clattering coming from the alternator, besides the bearing, it could be the voltage regulator brushes that may be worn down to the solder joints or came loose. You may need a new Voltage Regulator. If the brushes of the alternator, then you need a new alternator or a rebuild. Either of the two is most likely the cause of your stalls, a scrapping fan would not stall your car or cause the alt light to come on unless it seizes or drastically slows the alternator down enough to throw the alt light.

+1 do not over tighten the belts, For OEM fan belt it is 3 in 3 out for the shims and for the Conti Belt 1 in 5 out. The AC belt should be 3/8 deflection. If you over tighten them, it can also damage the Cam Pulley fitment and Shaft, possible #8 bearing leak (a very expensive fix)

Good Luck,

Jim
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Old 02-10-2015, 09:31 AM
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Quote:
Originally Posted by Upier View Post
I just had a similar problem. The fan would sometimes hit the housing. I took it out and discovered that the rear plastic cap had fallen out. It showed me that the rear bearing was bad , lots of play. The cap was keeping it centered sometimes. You need a new alternator. I just installed a Bosch rebuild last night. Works great now.
This is true. It happened on my 964.
The plastic sleeve for the rear bearing was cracked or loose causing the alternator to droop.
You can buy the plastic sleeve and the bearings from alternator parts houses.


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Old 02-10-2015, 12:16 PM
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