noise from smog pump?

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Dec 17, 2006 | 02:57 PM

Kool88vette

Thread Starter

Drifting

Joined: Oct 2006

Posts: 1,934

Likes: 3

From: Citrus Heights California

noise from smog pump?

My 88 is running great but I have a small problem. I have noticed a clunking noise and I am almost certain it is the smog pump. The alternator and water pump are new. I'll get a stethascope and listen to everything in that area. It sounds like a very slight bearing knock but it only happens at idle. When I accelerate it stops. I noticed it right after I installed my 1.6 Comp Roller Rockers. I hope it's not the RRs. It now idles like it has a cam. But there is a little bit of a noise from the smog pump area. I noticed there are 4 bolts behind the pump. It looks like I can take them off without removing everything. If I remove the 4 bolts I think the moving parts will come out. Can I gut the smog pump with it on the car? I can't delete it because of Cali laws.

Last edited by Kool88vette; Dec 17, 2006 at 06:49 PM.

Dec 17, 2006 | 10:14 PM

raisinbran

Instructor

Joined: Feb 2006

Posts: 165

Likes: 1

From: rowlett tx

You can take a broom stick and touch it to different areas of the engine and to your ear and hear what is making noise.

I dont think you can gut the air pump with it in the car, but you can take it out, gut it, and put it back in without anything looking different. See tech tips.

Dec 18, 2006 | 09:15 AM

GIJoe

Team Owner

Joined: Jun 2001

Posts: 26,196

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From: Orlando FL

St. Jude Donor '08-'09

Sounds like the smog/AIR pump is going bad.

Yes, you can completely gut it, just make sure the pulley is still good. That's all that's needed for the belt

Dec 18, 2006 | 03:01 PM

Kool88vette

Thread Starter

Drifting

Joined: Oct 2006

Posts: 1,934

Likes: 3

From: Citrus Heights California

Thanks! I'll gut it.

Dec 18, 2006 | 08:52 PM

86PACER

Le Mans Master

Joined: Jan 2003

Posts: 5,858

Likes: 7

From: Santa Maria CA

https://www.corvetteforum.com/techti...=261&TopicID=2

Since you are in CA, by gutting it and leaving all the plumbing attached for smog, nobody but you will know it's gutted. If you want to be able to put it back to operational, pull out the bearing race and remove the carbon fiber fins in tact and save them.

Dec 18, 2006 | 10:19 PM

SunCr

Le Mans Master

Joined: Dec 2000

Posts: 7,839

Likes: 22

From: San Diego, Ca

But you'll need a more efficient CAT to pass. Hmmm, $50 Bucks for a rebuilt pump or $300 for a new CAT, hmmm. . . .

Dec 18, 2006 | 10:35 PM

86PACER

Le Mans Master

Joined: Jan 2003

Posts: 5,858

Likes: 7

From: Santa Maria CA

Quote:

Originally Posted by SunCr

But you'll need a more efficient CAT to pass. Hmmm, $50 Bucks for a rebuilt pump or $300 for a new CAT, hmmm. . . .

Not really. See my post. You can save the internal fins and put it back together if desired and you don't have to buy either a new pump or a new cat.

I've left mine gutted two times now and passed just fine. I just show up with engine hot after a good drive.