Stones in exhaust

[Viperz888]

My friend has some stones or gravel in the backbox of her Ka. As it is a one piece exhaust, taking it off to shake them out will take a few hours so we might not bother.
Are they likely to do any harm? Is it worth getting them out? It only makes a noise at anything over 60, so isn't a problem to us, unless it will create problems down the road.
Cheers

[Defcon5]

Been in the gravel trap has she? Tell her she needs to turn in and power out of the slide next time.

But no, they wont do any harm - try going up a steep hill at max rpm to blow them out or something?

[Viperz888]

No idea whats happened. They don't sound big, and I did think about drilling a hole in the bottom but I'm not sure how I'd fill it again.
Cheers mate!

Edited by Viperz888 on Saturday 14th May 21:47

[Rich_W]

ARe you sure it's stones and not the internal baffles that are rattling around inside? Or even worse the CAT's broken up and the bits have gone down the pipe.

[Dogwatch]

Rich_W said:

ARe you sure it's stones and not the internal baffles that are rattling around inside? Or even worse the CAT's broken up and the bits have gone down the pipe.

My thoughts too.....

[rhinochopig]

Dogwatch said:

Rich_W said:

ARe you sure it's stones and not the internal baffles that are rattling around inside? Or even worse the CAT's broken up and the bits have gone down the pipe.

My thoughts too.....

Indeed, if it's a collapsing cat she could be looking at a sudden blockage at high revs which could result in bent valves. Happened in my old Mi16.

[Viperz888]

No, I'm not sure it's stones, but it sounds like them and the only way to check would be to get them out somehow. Is a collapsing cat likely on a 2004 model? They are in the rear box which is a silencer, which is far less important than the car imo.

[Baffled Spoon]

Depending on the type of silencer, these can still break down internally. I had the internal baffles break apart on the inside of my back box on a previous car, and it caused a rattle at certain rpm.

[rhinochopig]

Viperz888 said:

No, I'm not sure it's stones, but it sounds like them and the only way to check would be to get them out somehow. Is a collapsing cat likely on a 2004 model? They are in the rear box which is a silencer, which is far less important than the car imo.

We have a sportka, on a 53 plate which needs a new cat because it's had it. The body is covered in rust - to the point where the rear wiper has fallen through the outer skin. They are basically utterly ste when it comes build quality. The only reason we've kept it so long is because it's one of the most entertaining FWD cars I've ever driven.

So you yes it could be the cat, and to be honest it doesn't take much to damage them even on a newer car. Douse a hot exhaust in a flood and the thermal shock can cause damage.

ETA normally the emissions light will be on though first.

[Viperz888]

Ok chaps, looks like its an exhaust off job, just to be sure.
Do Ka's need new exhaust bolts for when you put it back on like Fiestas?

Thanks all muchly