Little noises and aggrivation

RAC91SC

Registered User
I changed the accumulator and finally I hope got the abs figured out... along that long process I have been noticing little noises. the ones I want to investigate include: a noise from the supercharger, a rattling, and a clicking in the dashboard.
1) the Supercharger is making an almost grinding noise that is kind of a hum. if that makes sense. the sound isnt really a concerning sound though.
2) There is a rattling noise coming from underneath the car. sounds like it may be a a loose heat shield or loose guts in a catalytic converter.
3) sometimes while driving there is a clicking in the instrument panel like the sound of the alarm bulb flashing when the door is open.
 
Opposed to rocks I would say marbles. It's a smooth noise. Like the sound a marble spinning in a cup or funnel would sound.
 
Hmm.

Opposed to rocks I would say marbles. It's a smooth noise. Like the sound a marble spinning in a cup or funnel would sound.

I would say normal on the SC. could be a bad bearing. Have you checked the SC oil level? I would.

Noise 2. Likely axactly what you said. You have to get underneath it and shake thing to find it. I had the original vats go bad and rattle on my 90.

Noise 3. Speedometer is the only thing that moves under there. What you describe sounds electrical, maybe. Could be a contact make and braking a connection. Look at the lighting circuits.

Other than that kinda need to be there to get a better understanding.
 
I am not certain about noise 2 and 3 but if you want to rule out the supercharger disconnect the belt and start the engine. If your marble noise is gone then you know it is the supercharger.
 
Well I checked the oil level and It was low but not dry. I drew out the remaining oil and fully changed it. It is now full of new fresh oil and the noise still hasn't changed. Do they make a noise generally? This is my first supercharged or turbo vehicle. But in bearings I have heard in the past they have sounded rougher than this.
 
I am in ems and healthcare I have a stethescope haha. What exactly do I listen for I.e. good sounds? Bad?
 
I am in ems and healthcare I have a stethescope haha. What exactly do I listen for I.e. good sounds? Bad?

Whatever noise you are hearing will simiply be amplified. Move it around from the snout to the rotor gears and see where the noise is the loudest. That will help tell if its the spring for the gears or the bearing for the snout.

If you move it to the hat and its worse there then you may have to rear it back on the rear bearings and listen to them.
 
Why not just pull the belt off to see if the noise goes away? It's easy enough to do. Disconnect the belt, start it back up and see if the noise is present. If the noise is gone with the SC belt disconnected then the noise in the SC.
 
Why not just pull the belt off to see if the noise goes away? It's easy enough to do. Disconnect the belt, start it back up and see if the noise is present. If the noise is gone with the SC belt disconnected then the noise in the SC.

I prefer to find where the location of the noise is. If its the SC you still have 5 or so parts that could be causing the noise.

These are just suggestions. Personally, taking it to the shop and letting someone else work on it is starting to sound like a better idea to me the older I get. ;)
 
Opposed to rocks I would say marbles. It's a smooth noise. Like the sound a marble spinning in a cup or funnel would sound.

Its the couplerfor the snout to the actual rotor pack. that marble sound is your rotors touching, I would get it fixed soon. You can buy a coupler off ebay fairly cheap and they are easy to change but the entire supercharger needs to be removed. If you need help with it pm me.
 
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Does a problem free supercharger make a noise at idle? Or just the whine upon acceleration? If so. What should it sound like. It seems to be coming from the top where has 3.8 casted. I'm assuming that is the hat? Maybe haha. Like I said. My first supercharger.
 
Before you continue to do more damage to either your supercharger or engine, whatever may be the issue, disconnect the sc belt and start the engine. This way if it is the sc then you can pull it off or if it is the engine you are not causing any further damage.
 
Noise

You asked several times if an SC makes noise. Yes. It is not unlike what you describe. It is not super loud. Other than the engine it is the rotating mass that makes the most noise. One guy thinks it is your rotors touching. Could be if it super loud. What would make rotors touch? Really bat and super noisy bearings or it has been off and someone did not index the rotors correctly.
Really what you need to do most is pm Davec. I believe he said he could help. Let him have a listen. Or post recording of the sound.
 
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