Forced Induction Question for guys with KB blower

[Clayton302]

So I took my 2.1 KB off and sent it off for rebuild after noticing a bit a growling/grinding coming from the head unit. I did all the normal stuff like checking to make sure the noise wasn't coming from any other areas before assuming it was the blower. It wasn't crazy loud but I could hear it resonate in the car and it was slowly getting worse. So the re builder did find two bad bearing in the front of the blower and preformed a full rebuild. Anyways got the blower back and the noise is still there or possibly returned after about five minutes running (I didn't notice it right away anyways). It is not as loud as before but it's there for sure. I stuck a screw driver up to the drive snout area and I can hear a definite growling/grinding noise. I stuck the screw driver to all other pulley in the area and they are quite or normal bearing sound. My question is could this be normal? Do you guys with 1.7s or 2.1s have the same noise coming from your head unit? Maybe just normal gear noise? With shipping I'm into this rebuild about $830 so I'm a bit unnerved over the whole thing.

 

[trinity_gt]

My 1.7 twinscrew sings it own stupid song at certain points in the RPM range:



I sent it out for rebuild (new bearings, seals etc etc), got it back and have the same noise. Beginning to question my sanity or whether the noise is even coming from the blower...

I do notice some rather unseemly noises from the rear of mine (near the throttle body) if I put an ear to it but after the rebuild and knowing everything is new, am ignoring it until I start actually running over shiny parts. It's just way too expensive to ship the thing around the continent...

It boosts fine and the rumbly noise(s) has gotten no worse so I'm going to chalk it up to normal. As for the noise in the video, I literally have no hair left from tearing it all out trying to figure that one out...

 

[Clayton302]

Sorry to hear about the hair loss. Yeah it's super frustrating to have a noise that could mean possible failure soon or just mean "yep its spinning normal". I'm glad to hear that I'm not the only one going nuts over this. Maybe I'll post a video. As for the noise in your video, I hear it but it sounds pretty normal. I have the 2.1 and I hear that noise sometimes as well.

 

[Gearbanger 101]

It's probably normal. The Eaton on my Allen kit used to make a little extra noise at times. It turned out to be the blower noise (harmonics) resonating through the intake. It got louder when the car warmed up. If I popped the hood and put my hand down on the intake lid, it cut the sound of it by 2/3.

 

[Clayton302]

I wish it where a harmonics style noise but its more of a grinding noise. At the same time I don't want to over analyze it, not that I've been know to do that . After work today I'll put a video to see what you guys think.

 

[Gearbanger 101]

I wish it where a harmonics style noise but its more of a grinding noise. At the same time I don't want to over analyze it, not that I've been know to do that . After work today I'll put a video to see what you guys think.

I hear ya. Take note though, the slightest grinding noise will be amplified through the manifold and intake track....so it may not be as bad as it sounds.

 

[Clayton302]

Looks like the 2.1 KB is coming back off and getting sent back for inspection. Video isn't that great but the audio is what I was after and you can really hear it making some funky noises.