If your exhaust sounds like it has a golf ball....

If your exhaust sounds like it has a golf ball rolling around inside of it, what does that mean?

When running it doesn't seem to pose a problem (I don't think), but I was changing the back breaks yesterday and bumps the exhaust, and I could swear it sounds like there is a golf ball rolling around inside.

Ideas? Is it just fine? Will it explode? Does this prove the existence of aliens?

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Earendil
If your exhaust sounds like it has a golf ball rolling around inside of it, what does that mean?

When running it doesn't seem to pose a problem (I don't think), but I was changing the back breaks yesterday and bumps the exhaust, and I could swear it sounds like there is a golf ball rolling around inside.

Ideas? Is it just fine? Will it explode? Does this prove the existence of aliens?

could it be the catalytic converter?

Since I have neither a problem with, or money to burn on, a new exhaust system, I have yet to bother with understanding the system all that much.

That said, I believe the cat is upstream of muffler in a distinctly different and self contained unit, in about the middle of the car. The sound I describe is definitely coming from the center of the last large metal container near the rear end of the car, only a couple inches from the rear bumper. I believe this to be the muffler :-)
Sorry I wasn't more descriptive in my original post. In my mind I made "exhaust system" synonymous with "muffler", when really there are (or can be) multiple pieces to such a system.

I don't pretend to know how exactly a muffler does it's job, but I wouldn't have guessed that there were objects within that, even if they broke off, would be spherical in shape, enabling them to roll around.

If someone actually put an object up my tale pipe I'm going to start carrying a large stick around with me...

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Earendil
If someone actually put an object up my tale pipe I'm going to start carrying a large stick around with me...

this should be your plan, then. so if you go to the back of your car, grab the tailpipe and start swinging the muffler around, you can make the same noise, right?

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daniel

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Earendil
If someone actually put an object up my tale pipe I'm going to start carrying a large stick around with me...

this should be your plan, then. so if you go to the back of your car, grab the tailpipe and start swinging the muffler around, you can make the same noise, right?

That is actually the only way I do hear it. With the car running, I don't notice anything too unusual. If the exhaust sound has changed since I bought it, it has been gradual enough that I haven't noticed.
As I hinted at, I initially noticed because I bumped the exhaust pipe when I was changing the back breaks. The muffler hangers are worn and loose, so it had enough swing that when bumped, it moved side-to-side allowing for "the golfball" to roll around. I then grabbed the tail pipe and rattled it around and could hear something rolling around inside. If I hadn't bumped it, I never would have thought to inspect the muffler.

I don't suppose it's hurting anything... I'd just like to know if
A: It's a sign that my muffler is shot, and I should start budgeting, or
B: There is no way it should make that sound, someone has stuck something up my tail pipe, and I should be concerned that it could cause a blockage and bring about damage.

But I guess at this point the two of us are just shooting the breeze
Anyone on these forums know anything about mufflers? Don't make me go find a river forum and ask them :tongue:

Cats come apart and wind up the rear section.

Yep, we found three cat gonads in the Honduh muffler...well that's what they looked like

The muffler on the iX had completely rusted out inside and sounded like simbas when you jostled it. For some strange reason, it didn't get loud until one of the tips fell off

i would just have a new muffler welded on if you are sure its the muffler.

Yes, but if the converter is coming apart why not fix the source of the problem? Mileage on the front pipe?

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rkj
Yes, but if the converter is coming apart why not fix the source of the problem? Mileage on the front pipe?

Quite honestly I have no clue what kind of miles are on the Exhaust system. When I bought the car 3 years ago, there wasn't any paperwork on it, though it apppeared it relatively solid shape. Now, on closer inspection I see some rust on the very bottom of the muffler, something I've never seen anywhere else on my car (and is an odd thing for the inland northwest). So I presume that the muffler at least is far from new.

Are there any at home tests for a CAT & Muffler system? I've never come across anything I don't think, but then as noted, I've also never cared

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Earendil
I have no clue what kind of miles are on the exhaust system.

Inside the catalytic converter, the exhaust stream flows through a ceramic honeycomb structure. If the catalytic converter gets hit by a rock or it simply dies of old age, it is possible to shatter that ceramic structure and have bits of it blow right out the tailpipe. Or worse, it can get turned sideways blocking the exhaust flow.

Viewed end-on, you should be able to see right through the honeycomb. Otherwise the outer surface of the honeycomb is curved to fit the contours of the converter housing. If a piece of it is now in the bottom of your muffler, it is possible that it will rock back and forth sounding like a golf ball in your muffler.

Great shots Ferdy, I had one come apart at 150k and on the way home from North Carolina to new york, the car, about half way, would not go over 40-50 MPH. It really got iffy the last 20 miles.... Just made it.

Looking at the pictures Ferd posted, and considering the symptoms posted under the "swine flu" thread, makes me think the whole swine flu episode was due to the stuff that's in the muffler now working it's way down the pipe. It looks like it might be a good time to start shopping for a new exhaust system.

Give the catalytic converter a couple of smacks (when it's cool). Do you hear anything rattling around in there?

John

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John Yust
Looking at the pictures Ferd posted, and considering the symptoms posted under the "swine flu" thread, makes me think the whole swine flu episode was due to the stuff that's in the muffler now working it's way down the pipe. It looks like it might be a good time to start shopping for a new exhaust system.

good thinkin!

If you don't have the money for a new cat, I have taken them and removed the remainder of the catalyst material. Then welded a new pipe in the middle to make a "test pipe." Keep in mind this is not legal and probably will not pass smog inspection but it can save some money for a short time. The pipe in the middle prevents odd back pressures from the air flowing into different sized chambers. Also don't buy a cat from the muffler shop you can get one a high flow cat at auto parts store much cheaper and have it installed at the muffler shop usually for less then their cat or especially a BMW one.

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jl1371
Also don't buy a cat from the muffler shop you can get one a high flow cat at auto parts store much cheaper and have it installed at the muffler shop usually for less then their cat or especially a BMW one.

Well, that used to be more true, these days a new front section isn't that much, last one I bought from BAV was 300 or so. You start welding all those pipes together and you'll wind up spending just as much, unless you hack in a new converter into the old down pipe. That doesn't make much sense either.

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rkj

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jl1371
Also don't buy a cat from the muffler shop you can get one a high flow cat at auto parts store much cheaper and have it installed at the muffler shop usually for less then their cat or especially a BMW one.

Well, that used to be more true, these days a new front section isn't that much, last one I bought from BAV was 300 or so. You start welding all those pipes together and you'll wind up spending just as much, unless you hack in a new converter into the old down pipe. That doesn't make much sense either.

jus to help with price comparisons, i just had a headers-back exhaust built for my car with a new cat and muffler (2.5in tubing) for $700 total. the cat and muffler were magnaflow, and i think they were about $200 each.

Gotta remember that for the next time somebody quotes me $750 for just the muffler :X

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daniel
unless you hack in a new converter into the old down pipe. That doesn't make much sense either.

jus to help with price comparisons, i just had a headers-back exhaust built for my car with a new cat and muffler (2.5in tubing) for $700 total. the cat and muffler were magnaflow, and i think they were about $200 each.[/quote]

When they built your system did they crush bend the tubing or use mandrel bends?

I was just on partstrain.com they usually have good prices and I can get a bolt up cat for $300 or one that needs to welded in for $67 for a magnaflow.

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jl1371

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daniel

jus to help with price comparisons, i just had a headers-back exhaust built for my car with a new cat and muffler (2.5in tubing) for $700 total. the cat and muffler were magnaflow, and i think they were about $200 each.

When they built your system did they crush bend the tubing or use mandrel bends?

I was just on partstrain.com they usually have good prices and I can get a bolt up cat for $300 or one that needs to welded in for $67 for a magnaflow.

mandrel bends. it took them a whole day to build it. it sits as close to the bottom of the car as possible without touching anything. really nice work.