Should the smog pump (air pump) make a loud roaring noise while it is running? Will a new pump run quietly?

 

There is a muffler on the smog pump connected by a hose. Make sure the hose hasn't deteriorated or vibrated off.

 

My original went bad and then a rebuilt Cardone went bad as well.......

Both times it made a rack Rack RACK Rack rack sound....put a long screwdriver on the housing and then place your ear to it...you'll know if it is the pump

And yes, swapping it out fixed it right away.

 

This kind of reminds me of the problem that I had last year with my 87 only it was not noise related.
I took a friend to a Bank and when she returned the old C4 wouldn't start.
Having AAA is a plus and called them thinking I had bad battery. They attempted to jump start it several times with no luck as the engine would barely turn over.
Ended up towing it to my friends house then used her car to buy a new battery
Installed the new battery and still the same.
My brain for some reason or other said it must be the starter to I went to my parts supplier and got a new one.
Before I left, he asked me how many miles on it which were in excess of 122,000 but less than 2,500 on the new 377 stroker engine.
Told me before I changed the starter to check the smog pump first which I thought was strange. Hooked up the battery charger once again then have a friend try to start it as I watched and noticed that the serpentine belt was slipping oh so slowly.
When I touched the smog pump, it was hot as hell.
Removed the belt and it fired right up.
Seemed like the old emissions pump had seized up and was the cause of it all.
Just thought I would pass this on to anyone who may run into a similar problem so don't over look the not so obvious.

 

same thing happened to me. However it happened with the replacement one. The original one was making a slight noise and I thought I would change it. Should have left it alone or better yet gutted it.

 

I had put a 45k mile smog pump on my 89 after I seized the one that was on there with water.

After the car gets warmed up, and I park it. When I go back out, I hear a noise from the front of the engine that goes away after a few minutes. If I then park the car, then come back out and start it. The noise is there then goes away after a few minutes.

I took my scope all over the place and couldn't find the noise. But I used my ear this last time and it seems the noise is coming from the smog pump. Though for some reason I don't hear the noise when I put my scope on the smog pump.

Do you have any torque specs for the pulley bolts, pipe bolts, and hold down bolts I can check to make sure they aren't the problem?

It just seems odd that this noise only happens after I start it when the engine is warm, then goes away after a few minutes. I would all the noise a soft rattle or something as it isn't a buzzing type noise.

 

They are supposed to make a little noise after you first start the car, its normal

 

The thing that is weird is I've had this used pump on for 4 months with no problem. Then I decided to pull the frisbee off and put on a new belt since the old one was stretched because the PO put on a longer tensioner than stock. I had replace the tensioner to an OEM one last year.

Well, after that I noticed the front compressor seal started leaking oil and spraying the hood. So, I figured I'd put the frisbee back on to see if that would help. And then right after I had put the frisbee back on, I noticed the noise at a warm start up. Months later I pulled the frisbee again and the noise is still there.

It only makes the noise on a warm start up. It just never done that before, and the original pump didn't do that either.

Anyone have the torque specs for the bolts that go on the smog pump? I figure it wouldn't hurt to check and make sure they are torqued.

If this is normal, then is it normal to hear the noise when you get in and start it? Or are you only supposed to hear it when you put your ear up to it? I only hear the noise at idle, once I hit the gas to go, I can't hear the noise anymore. Which I guess either the noise goes away, or the engine noise blocks the smog pump noise. Then when I stop at a stop light, I can hear the noise again. But after a few minutes after start up, the noise is gone.

 

I got tired of all you see written here and just gutted it. And while you have it off, take a wire wheel and polish it. Looks like chrome when done.

It's been gutted for going on 5 years and guess what? No more noise!!! And the car runs fine.

 

 

I'm thinking that noise is NOT normal. As I can hear it when I start it up after the engine is warm, and hear it when I'm sitting at a stop light. But it does go away after a couple of minutes. I've read the noise means the pump is going out. Though mine isn't a whine or ticking noise I've heard others mentioned. More of a soft rattle.

I'm thinking of putting the old one back on and see what that does. It did start to sieze when I got it wet. As I noticed the pulley was getting harder and harder to turn as the days went as I had been cleaning the engine. I pulled the smog pump off, and was able to get it to turn like it should.

I sure would hate to get a reman one, put it on. And it makes a noise and have to keep swapping them out.

By the way, how are you guys gutting them? I had my old one apart, but didn't see a way to take anything out of it.