If more tension doesn't help, I'd replace the belt and be sure to clean the pulleys with brake cleaner or a degreaser. Old belts tend to dry out and loose their grip.spacecad3t wrote: Sun Jun 07, 2026 3:45 pm Following up here as I finally got around to testing the belt squeal. I spray water on it, immediately quiets up. Must be too loose still? Or maybe galled from old pullies? Im going to try and add a tiny bit more tension this week and see.
AC/Alt Belt Tension
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Tom
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spacecad3t
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Thanks Tom. I should have probably cleaned the pulleys during the Alt/Belt change, as it is a new belt, and if its oily now, then yeah- I'll have to put another new belt on.Tom wrote: Mon Jun 08, 2026 6:51 amIf more tension doesn't help, I'd replace the belt and be sure to clean the pulleys with brake cleaner or a degreaser. Old belts tend to dry out and loose their grip.spacecad3t wrote: Sun Jun 07, 2026 3:45 pm Following up here as I finally got around to testing the belt squeal. I spray water on it, immediately quiets up. Must be too loose still? Or maybe galled from old pullies? Im going to try and add a tiny bit more tension this week and see.
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spacecad3t
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I think this is sorted now. My rebuilt alternator had a spacer in place that had the belt misaligned by a single groove... Had to pull it all back out to remove that. Took the time to clean all the pulleys, test their bearings by spinning them, and installed another new belt. Went slightly tighter than before, no squeal.
Some photos for future reference.
Some photos for future reference.
- IMG_3165.jpeg (3.2 MiB) Viewed 8 times
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- IMG_3173.jpeg (2.65 MiB) Viewed 8 times