Exhaust rattle

[CraigHew]

After about 10,500 miles, my Mega S2000 has developed a (slight but noticeable) exhaust rattle.  The rattle occurs consistently at 2800 / 3000 rpm, which is a little annoying when pootling around but hardly an issue when "pressing on"  I'm thinking I need to just get used to / live with it, but then I wondered if my exhaust was repackable?

Its got SS allen head bolts at the end.  Is it simply a case of removing the bolts and prising the end off ?

So, repackable or not, how do you tell?

[Luapno]

It is repackable, it could be the Cat loose or the perforated metal tube that runs down the middle.

[CraigHew]

Thanks.

It's certainly not the cat as that is located in the link pipe between the manifold and the silencer.  Well technically that's where the cat goes, it's actually on the garage shelf as I run a decat pipe.

[Luapno]

Perforated tube it is then, they tend to expand a bit and rattle on the front and rear connections within the can. (mine does).

Its a messy job repacking make sure you wear gloves and a mask the fibre glass gets everywhere

[Hornet600]

Might not need re packed. I had same issue. I just slightly bent the inner pipe at 6 and 12 o'clock marks to make it tight against the sleeve. Stopped the rattle. Good luck 

[Man On The Clapham Omnibus]

9 hours ago, Hornet600 said:

Might not need re packed. I had same issue. I just slightly bent the inner pipe at 6 and 12 o'clock marks to make it tight against the sleeve. Stopped the rattle. Good luck 

I have the same issue with my Wunoff box. As you did, I squeezed the perforated tube to make it bind on the spigot but because the tube is fixed to the cap that comes off, you always have difficulty re-engaging it with the spigot down a long dark hole. Making it less that a sliding fit exacerbates this problem. I spend a frustrating half hour trying to get the tube to mate with the spigot only to find that it still rattled. Next time, if I can be bothered, I'll put dents in the tube about half to one inch from the end so that there's still an oversized 'mouth' to fit over the spigot before it binds on the distorted section. Luckily, the resonant period does not coincide with the 4500 rpm required for a sound test at track days!

[jonjh1964]

I've have the same problem and agree with the other posters that have pointed to the perforated tube rattling on the end cap pipe.  I've tried various things: wrapping the perforated pipe in aluminium tape, jamming in a stainless packer sheet etc with little success, my final solution is exhaust paste and putting in a slight crimp in the perforated tube.  It's still not perfect and I re-do it annually (at MOT time when I have the exhaust off to refit the catalyst) and can live with it until I have to replace the exhaust when I'll be going for the biggest Simpson box I can fit (I might even get them to make me a smooth 4-2-1 manifold to go with it).

[Thrustyjust]

Could be the wadding has burnt away from the tube and allowing movement. Just repack with a CBS refill kit if thats the case.

[Man On The Clapham Omnibus]

Mine did it from new. Wunoff chaps said send it back but it's heavy and they're in Bradford so I didn't bother. They suggested silicone sealant but frankly I don't think it could take the temperatures. 

[Andy (Sycho)]

Craig, mines exactly the same it's the perforated pipe at the rear. The front is welded but the rear just is pushed in, I've silicone mine in with high temperature silicone several times.

I also had it so it sounds like I had a bag of bolts in there, which was the exhaust past that had gone hard & fell into the can. 

[Ian Kinder (Bagpuss) - Joint Peak District AO]

This should be suitable. I've just used it on the manifold to link pipe slip joint to fix a slight leak: http://www.jb-weld.co.uk/j-b-weld-gasket-maker-sealant/j-b-weld-hi-temp-red-silicone

Are you sure it's not the spacer between the exhaust hanger bracket and the chassis moving?

 

[BenD]

i went the otherway to everyone else and repacked my exhaust the original wadding fell out as i turned the can on its end. repacked with acoustafil and ive had no problems since

[CraigHew]

2 hours ago, IanK said:

Are you sure it's not the spacer between the exhaust hanger bracket and the chassis moving?

Thanks Ian, fairly sure but will re-check before I pull the can off

[CraigHew]

2 hours ago, bunje said:

i went the otherway to everyone else and repacked my exhaust the original wadding fell out as i turned the can on its end. repacked with acoustafil and ive had no problems since

@bunje, was your acousta-fil the fluffy blanket type or the stuff that is very thin when you put it in but expands up to size when heated?

[Ian Kinder (Bagpuss) - Joint Peak District AO]

1 minute ago, CraigHew said:

Thanks Ian, fairly sure but will re-check before I pull the can off

It would be interesting to see pics of the contents of the can. Others have found all the sound deadening has gone. I'm sure mine's got nosier with miles. Others took some of the wadding out from new to make them louder!