Lately, I have heard many people talk about strange noises coming from the engine / blower. Mine developed a noise similar to loose marbles rolling around in a coffee can shortly after my lower pulley was installed (2#). When it was in for service, I asked them to check it out, and they determined that it was a bad bearing in the blower. The blower was replaced, and now, 5,000 miles later, it's back. I haven't checked to see if the two pulleys are indeed not in line with each other, but that would be my guess since the bearings are going bad.

My question is this: How many people here have experienced a noise similar to this after installing a lower pulley?

 

I have a small noise that resrmbles what you are describing that
comes and goes with my truck, expecially when I am in park and the truck is first started. I have listend rather intensely to it, and it
appears to me to be an air related issue, coming from the MAF area. Goes away and has not been an issue.
Hope this helps some.
Marc

 

Sounds like this is your problem:

Q- I installed one of your supercharger pulleys, and now I notice a strange sound coming from my supercharger. It almost sounds like marbles rattling in there, or a little like a diesel engine. What's going on?
A- This is a common situation, and is due to air cavitation within your supercharger (think of it as air bubbles bursting). By burning your chip for a slightly higher idle speed, we can overcome this problem. By the way, it is not something that would cause damage.

Thac came from JDMs FAQ on their webpage. Here is a link:
http://www.teamjdm.com/id23.htm

 

Putting a new pulley on is pretty much a "no-brainer". If not, I might not have been able to install my total(so far) of three . If the three bolts are torqued down evenly, it shouldn't/couldn't be out of alignment.

If, by some chance, they are out of alignment the belt would be wearing before the bearings. Look for rubber residue on the aluminum timing cover on the front of the eng. right between the two upper idler pulleys.

I've had no noises--yet.

Dan

 

Good point - I didn't even think about the belt wear.

If it is cavitation, what would explain the fact that the noise went away with the new blower, but now is back? Could slight misalignment between the two pulleys be enough to prematurely fail a bearing?

Marc - You have the exact noise that I do. Next time you drive it, try getting the RPM's as high as you can without getting into the boost. The noise I have is most noticeable there. When the truck is in drive and my foot is on the brake, the blower will make the noise (the new one hasn't started that yet).

Maybe all I need is a chip reburn for this issue. I thought about sending it back anyway to get the latest Superchip program... if they have one.

 

Like I stated earlier, mine comes and goes and I have already
concluded it to be an "air" related issue, which includes cavitation.
Mine goes away and really only returns when the truck is first started and is at a low rpm.
Marc

 

Low idle/super charger cavitation can be alleviated by your chip tuner. Tell him about it and I think they will raise the idle rpms a tad.

Dan

 

Thanks LIGHTNINROD.
My new program and related items arrived yesterday and will be
installed tonight.
Marc