A couple of questions
A couple of questions
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Discussion

doddze

Original Poster:

1,302 posts

268 months

Sunday 22nd May 2005
quotequote all
The mystery of the unusual rasping / vibrating noise from my exhaust continues and the 2 small splits I have found I have filled with no result .... so a couple of questions..

One of the clamps at the bottom of the downpipes as shown below appears to be touching the gearbox.... which could be the cause of the noise.
[pic]http://img.photobucket.com/albums/v644/doddze/exhaustclamp.jpg[/pic]
How much clearance do other people have between the exhaust and gearbox?

Also how easily does the exhaust seperate from the downpipes and what is the best approach? ...as I may need to take the system off from under the car to have a look at it as the noise is doing my head in :banghead:

woody

2,189 posts

313 months

Sunday 22nd May 2005
quotequote all
You could try changing the clamps the the 'jubilee' type (I used stainless steel ones from Demon Tweeks), this will also give you a few more mm ground clearance.

Chris

johns3

93 posts

259 months

Sunday 22nd May 2005
quotequote all
i too have the same problem, mine really rattles loudly. Sounds awful. Ive tried wedging things between as a short term bodge but doesnt really work. I will look at some different clamps too.

bridgdav

4,805 posts

277 months

Sunday 22nd May 2005
quotequote all
These are the Kiddies....

HERE

doddze

Original Poster:

1,302 posts

268 months

Sunday 22nd May 2005
quotequote all
I have moved the bracket round so it isn't touching the sump anymore.... although I think the exhaust may only have a few mm's of clearance!!.... still makes the noise.

I think the exhaust is going to have to come off for a closer inspection. s this as easy as two clamps undone two bolts by the box and one at the tail pipes and hope it will seperate from the down pipes Dont want to crack the down pipes or anything!!

Is there anything that could have come loose within the exhaust itself that would make the vibrating noise??

At tickover and revving on the drive it sounds fine... only when I am driving between 3500 and 4000 rpm's...

Also noticed a strange smell which is either the stuff I used to fix a samll crack burning off or I guess it must be leaking but it doesn't smell "exhausty" just stinks!! Maybe a rat crawled in the tail pipe


bridgdav

4,805 posts

277 months

Sunday 22nd May 2005
quotequote all
It has been known for Oiks to put stones down the tail pipes....Grrrr, not happened to me :fingerscrossed:

The baffles inside the main box are prone to failing... they can be welded - a small inspection hole cut in, weld baffle weld hole back up.... Although whenever I've heard this done it still fails soon after..

Try and get it on a ramp, have a look / listen from the underside when revving....

doddze

Original Poster:

1,302 posts

268 months

Sunday 22nd May 2005
quotequote all
I had a look at the underside when it was ramped at kwik fit and couldn't see anything obvious.... baffles seem likely as the noise started after a very spirited run with some some very high revs and speed involved...but no big pot holes..

when I finally slowed down it was then I noticed what I thought was a rattle...

Would a major blastdown an A road be enough to loosen baffles??

It passed the MOT the next day so no major holes...

To be honest the exhaust looks like the original and the downpipes are half the width they should be so I have been investigating a new system... but that is a question on the new thread I have just posted

gefopsman

260 posts

268 months

Monday 23rd May 2005
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I had this problem on my old exhaust. I cut open the silencer expecting there to be an obvious problem. There was actually very little that could go wrong, and certainly nothing which could cause the vibration/rattle. I came to the conclusion that there must be something in the oval section leading up to the silencer.

I just replaced the system as it was easier.

I may still be able to source the old unit from my ex wife if anyone is interested in opening up the oval section to investigate.

TOPTON

1,514 posts

265 months

Wednesday 25th May 2005
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I had the extra noise on mine, only happened when revs got up above 3k. tried lots of fixes, like changing the clamps and new bobbins, cutting open the silencer box to inspect baffles, but non helped. Turned out to be the silencer box itself. The steel was too thin and it was resonating like a biscuit tin lid. I cut it away and welded on some thicker steel. Problem solved.

doddze

Original Poster:

1,302 posts

268 months

Wednesday 25th May 2005
quotequote all
The noise only started after a blast down a main road so I am pretty sure it is a baffle problem... I am looking into a new system as the down pipes are about half the diameter they should be and the whole system appears to be the original one so it is now 14 years old

watto

66 posts

257 months

Wednesday 25th May 2005
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bridgdav said:
These are the Kiddies....

HERE



Just what I need to stop bottoming out. Do you know what dimensions to replace the 2 clamps beside the front box?