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Whining noise when starting up

 
Old 08-26-2018, 11:44 PM
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st0ppy
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Default Whining noise when starting up

Hi there!
I have a 95 968 - runs great. When I start it, hot or cold, it makes this 'whine'. It sounds like a belt or something needs tightening but not sure which. If I start and stop it a few times (running errands for example) it will start sometimes without the noise.

AC compressor and belt replaced few years back. Noise was there before the replacement.

Thanks for any help!
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File Type: mp3
startup.mp3 (101.2 KB, 25 views)
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Old 08-27-2018, 01:26 AM
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Eyeman
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Can't really hear it on your video.
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Old 08-27-2018, 01:49 AM
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Jfrahm
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Although I can't hear it in your sample, that whine is usually a slightly-too-tight balance shaft belt.
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Old 08-27-2018, 11:00 AM
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st0ppy
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Hey,
Thanks all - apologies for the video. Ill try to capture another however the noise starts at 2 seconds and ends at 3 seconds. Whine / grind maybe!? Hard to find an adjective to suit that noise.
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Old 08-28-2018, 08:45 AM
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thomasmryan
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an alt will spike a 20-30 amp output to bring the battery back up for a few seconds immediately after starting. check the belt tension and pulley alignment. belts do stretch with time/ozone.

the belt should be as tight as the timing belt. I go with 5mm deflection and then count turns to zero deflection on the turnbuckle. with the belt at zero deflection, tighten the belt further the same number of turns. then tighten the pivot and lock the turnbuckle and end points.
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Old 08-30-2018, 06:53 PM
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The startup sounds normal to me in your clip. Certainly doesn't sound like alternator belt squeal.
Post another clip from under the hood.
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Old 01-25-2019, 12:38 AM
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st0ppy
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Originally Posted by sublm8 View Post
The startup sounds normal to me in your clip. Certainly doesn't sound like alternator belt squeal.
Post another clip from under the hood.
Hi there,

sorry for the delay. Attached is a new clip. 16-18 is where you'll hear the sound.

Thanks a lot!
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File Type: mp3
pstart.mp3 (448.6 KB, 17 views)
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