FAQ: Supercharger Noise (Bad Coupler)

It's strange because it only does it when the motor is fully warmed up and at idle. It is a grinding type clunking noise. Has anyone had this before, the riv just went past 149xxx miles. I am also getting a lot of pully noise that I beleive is coming from the water pump. THanks.

Im sure that mine needs a new coupler but it (sometimes)only rattles when cold at idle. nevr when warm at idle or any time else

Alternator bearings will sound like that when warmed / hot when they are worn out.
Next time you hear it put your hand on either end of alternator and see if it very hot to the touch. Should not be.
Doing this with engine running and bad bearings you can almost feel the bearings growling in the case.
Worth looking at before you start condemning the supercharger. Also, put your hand on the end of supercharger snout while running and see if you can feel what your hearing. Just be careful of rotating pulleys and belts. An inexpensive mechanics stethoscope can be helpful sometimes if you you know what your listening for otherwise you'll just hear a bunch of magnified noise.
If you know you have a bad water pump, while changing it out check the play on all other rotating pulleys as well. It's worth the time and money to replace any questionable pulleys or tensioners while your in there.
Noises from that side of the engine can be difficult to pinpoint because of all the different rotating components. Have someone else that is mechanically inclined also listen. Two sets of ears can be better than one sometimes. Good Luck.

Our idler and tensioner pulleys are known to fail at half your mileage. Might be a good time to change your belts, too.

Belts have been changed. I put my hand on the topside of the supercharger and felt the "noise" if that makes sence. I will have my mechanic check it out while he is doing the hazard switch. Thanks guys.

FYI most mechanics just say 'you need a rebuilt supercharger' when in reality you only need the coupler replaced. Just make sure you and he are aware of it.

Hey Derek, thanks man. I know mechanics don't really like to fix a little thing, they would rather get their hours in by replacing the whole assembly. I will pull the belts off tomorrow night and check and see what is causing the noise.

another good way to zero in on the coupler if thats whats making the sound is to use a "poor mans auto stethoscope", a paper towel tube held to your ear.. good for closing in on engine sounds....

Another way is to use a long screwdriver with the head on the subject and the handle on your ear. The coupler is at the base of the stount.

what types of noise will the coupler make if its bad. It sounds like something is almost clunking around in the s/c...

a rattling sound like rocks tumbling around... a coupler cost $25-$30 at ZZP, Intense, WbodyStore, etc and is fairly easy to replace. When mine went out at 140k mi, it was most noticable when cold and would go away after warming up and at speed.

Yeah, it is def my coupler. I will have to order one. If nothing else, now would be a good time to replace the s/c fluid. Thanks guys.

I have a noise coming from my supercharger as well but I only hear it when I turn off the car. Is this likely my coupler?

rivman96 wrote:

I have a noise coming from my supercharger as well but I only hear it when I turn off the car. Is this likely my coupler?

Yes

rivman96 wrote:

I have a noise coming from my supercharger as well but I only hear it when I turn off the car. Is this likely my coupler?

That's almost exactly the symptom I had too. I could hear it a little bit at idle, but when I turned off the ignition it was very noticeable as the engine came to a stop. New coupler from ZZP and it's been purring perfectly for 2 yrs now.

Quick question guys. While stopped at a light or at idle I am hearing what sounds like a golf ball hitting the roof coming from under the hood. Any idea what this might be? When I bought the car I could hear a small growling noise coming from the alternator. I had the dealer look into it and they said they ran a line through the alternator and it's putting out full power. Let me know. Thanks.

The most common reason for this "marbles in a can" sound is a worn supercharger coupler, but it can come from other sources. You may want to loosen the SC belt, then move the SC pulley back and forth to see if there's any play. Read through this thread for more info. Good luck!

Common source for 'marbles in a can' sound is the water pump. As often as not they will get a bit noisy before they fail.

Also look for weak/broken rubber in the motor mounts and loose metal shields on engine and exhaust. Also look at the palstic engine "sight cover" to see if the little rectangular cup at the back is snug against the bracket on the engine; if not it may knock around a little.

Albertj

Do you and any other people here experience that mechanical noise emanating from the intake / supercharger when the engine is cold. I've been hearing it for a while but didn't correlate it to the 3.4 pulley drop I made after putting on the rockers.
I wasn't sure if it was a supercharger making the noise it will make at 100,000 miles and a coupler with about 1/8" play or not.
Figured I'd live with the noise until I put a New Gen 5 on it next year.
But if this noise is normal then I'm relieved. It goes away shortly after the SC warms up, and before the engine is up to normal operating temp.
I had gutted the air cleaner housing a long time ago and didn't get this noise then.

Whens the last time you changed out your SC oil?

Less than 10,000 miles ago.

Hmm, this growl, is it a humming noise or grinding? I have heard the bearings do make a grinding noise in the snout when they start to go, also like you stated the coupler is a common issue. But that doesn't sound like the problem here. I woodn't lose to much sleep over it if everything is working fine.

Yeh, I'm not losing sleep or getting too excited about it. It was just the first time I heard someone else mention noise from the supercharger, with a gutted airbox mention the type of noise I am hearing.
I had a certain noise from just gutting the airbox that's expected, now I hear the SC make noise when cold for a short time and then goes away. Like I said it will dissipate before the engine comes up to 1/4 it's normal temp. Generally by the time the HVAC blower starts to come on in the extreme cold weather we have been having.

Rickw wrote:

Eldo wrote:

And you know what, except perhaps for the cold-supercharger-growl in the morning,

Do you and any other people here experience that mechanical noise emanating from the intake / supercharger when the engine is cold. I've been hearing it for a while but didn't correlate it to the 3.4 pulley drop I made after putting on the rockers.
I wasn't sure if it was a supercharger making the noise it will make at 100,000 miles and a coupler with about 1/8" play or not.
Figured I'd live with the noise until I put a New Gen 5 on it next year.
But if this noise is normal then I'm relieved. It goes away shortly after the SC warms up, and before the engine is up to normal operating temp.
I had gutted the air cleaner housing a long time ago and didn't get this noise then.

I know exactly what you mean Rick. I've always noticed that when my engine is cold. I'm not sure it is the supercharger. Might it be the Idle air control?

Good point, I wasn't sure if it was the SC while in Bypass mode or something else.
All I know is that became much more noticeable this year and that is when I did the 1.9:1 rocker change as well as the 3.4" pulley change.