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Discussion Starter #1
I've been experiencing a weird 'clicking' noise under acceleration during the first 5 minutes after a cold start up. After it warms up, it kinda goes away.

I took the SC belt off to check the feel of the bearings.

Is it normal for the SC to make a little noise when you spin it by hand, or should it be silent like a new wheel bearing? When I spin mine, I hear a little bearing noise.

I've never spun another one, so I don't know.

I'm going to let it set all night, then drive it in the morning without the belt on to see if it makes the mystery sound.

Thanks
 

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Discussion Starter #2
Update

I drove the car this morning, but as I expected, when the engine is running, the SC still spins via the force of the air moving through the veins.

It still made the sound to a certain extent, but not nearly as loud. I'm thinking that the sound I'm hearing is still the SC bearings or something, and it's just louder when the belt's on and is being force driven.

What do you guys think? I still don't think the sound I'm hearing is normal... probably due for a snout rebuild maybe. The car's only got 65k on it though....
 

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when I had my belt off, turning the SC by hand was 100% silent, felt nice and tight tolerance. No play at all.

I had a SC that was off a M90 3.8L Ferd and it was knocky, had a lot of play in the snout. I would imagine it was fairly noisy.
 

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How many miles on the SC
Most common issue is the coupler
If its 80 to 115 K and the coupler has never been changed then thats probably what it is
 

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Discussion Starter #5
SC noise

The car only has 68k miles on it... and I don't think it's the coupler, because it doesn't have slack when you rock the pulley back and forth.

As for the the bearing tolerance, it's pretty tight and smooth when I spin it, it just makes a little noise back in the charger when I do.

As for the sound I'm hearing under boost, it's hard to describe, but imagine the rotors of the supercharger brushing up against the aluminum case... not a knocking, but more of a brushing, rotary sound.
 

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Check the tensioner/idler pulleys.

I lost 2 of them in 1 month when cold, when it was cold seems to be the hardest time in their life.
 
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