Exhaust back box diy replacement ?

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ellevie
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Exhaust back box diy replacement ?

Post by ellevie » Fri Mar 31, 2006 7:49 pm

My E Reg 19TRS exhaust back box needs to be replaced. The center box and the other pipes appear to be in good condition. In the past I have always had exhaust work done by fitters. I have a few quotes at around £20 for the box itself which is less that half the cost of having it fitted at around the £50 mark. Is it easy to get the pipe out of the center box ? How do I seal the new pipe into the center box ? Any advice on doing this as a DIY job would be much appreciated.
David

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Post by Way2go » Fri Mar 31, 2006 9:04 pm

When you watch the exhaust fitters using gas cutters to chop off the clamp & then after adjusting the flame heat up the pipe to expand it enough to free it, I question whether it is worth the aggravation to DIY exhausts. :cry:

Add to this that they have a comfortable workspace on the lifts and we are lying underneath with limited wrestling room. :?
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Post by AlanS » Fri Mar 31, 2006 9:07 pm

Unless you're a dab hand with a welder, I can't see you doing this as a DIY.
The back box is welded into the mid box (affectionately known as the strangulation box) and usually there's a bit of fancy plumbing involved in the process.
I recently did some running repairs on my Tri Estate which have exactly the same system and for starters, we had to remove the entire system right from the front spring loaded coupling back. It took 2 and at times 3 men close to half a day to remove, repair and refit the mongrel thing. I have had back boxes replaced by exhaust specialists in around half hour up on their hoists and using the right gear to fit it.
The quoted price overall is about on par with what I paid out here but having said that, the price of the muffler is about half of what we were charged so his parts price is down but his labour pretty high by comparison with the amount of labour needed to do the job for someone with a hoist and all the right gear at his fingertips.


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Post by ellevie » Fri Mar 31, 2006 10:42 pm

Thanks guys for the feedback. So it looks like the new and old parts have to be welded together which definitely rules it out for me as I don't have any welding kit or experience in using it. I searched Google for anything about it but couldn't find anything; I wondered if it was so easy that nobody bothered writing anything about it, but it looks like it's just the opposite. What got me thinking of doing it myself is that one of my neighbours replaced his backbox on his van on ramps by cutting the pipe with a saw and I didn't see any welding gear in evidence; I presumed he must have used some kind of special compound to do the join. I must ask him exactly what he has done, just out of curiosity. Thanks again for the advice.
David

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BX19TXD 150k K Reg

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Post by AlanS » Fri Mar 31, 2006 11:35 pm

We had to use a dremel and cut slots in the old pipe to get it off as well as use heat. Then it has to be flogged with a hammer and chisel to remove. The next problem is that the pipe is the same size as the muffler entry pipe so needs to be swaged and I don't know if it's just coincidence, but it seems all the exhaust parts are uniform on the BX but it seems the pipe sizes may vary as it always seems to be a case of pipes either going over requiring swaging or having to cut off at the muffler and welding into it. I'm basing this on having to do exhausts on a Trs, Tri, TZi, 16V and not one was simple and straightforward. :oops: :oops: :cry:


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Post by jeremy » Fri Mar 31, 2006 11:55 pm

What you ahev to ask yourself is'What are the chances that I can do the job with the tools at my disposal - and What the **** do I do if I get stuck?'

Exhaust sections using flange joints (2 plates facing each other with 3 or 4 bolts) are easy - cut the bolts with a grinder and hit it. clamp joints with a mushroom type fitting on one bit and a bell mouth on the other surrounded by a clamp aren't much more difficult, but one pipe going into the other can be very dificult. They are often easy with a pneumatic chisel or hammer but without - they are not, and without the right tools you have the risk of damaging the section you want to keep.

So you get half way through the job, after 2 days lying on your back with a couple of eyefulls of rust, 6 skinned knuckles soaking clothes - and various bits of cut-off pipe lying on your driveway - what are you going to do?

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Post by ellevie » Sat Apr 01, 2006 12:39 am

Jeremy said,
"...So you get half way through the job, after 2 days lying on your back with a couple of eyefulls of rust, 6 skinned knuckles soaking clothes - and various bits of cut-off pipe lying on your driveway - what are you going to do? "

Light up a Hamlet ?
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Post by Stewart (oily!) » Sat Apr 01, 2006 4:42 pm

on your 1.9 petrol the joint there is sleeved, on a diesel it would very likely just come apart with a bit of hammer action :D but as yours is a petrol one its most likely to be fused together, a mini grinder would cut away the outer bit, then a bit of swearing and hammering ought to see the box on the floor.
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Post by cavmad » Sat Apr 01, 2006 5:50 pm

Another alternative may be to buy the box yourself and ask a local garage, as opposed to a fast fit type place, to fit it for you. Obviously ask around for prices first but I can`t help thinking you`d be better off going straight to ATS or National Tyres (or similar) and get them to do it.
However on a personal note I`d sooner nail my b*llocks to the floor than use Kwik Fit (up).
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Post by Way2go » Sat Apr 01, 2006 7:57 pm

cavmad wrote:However on a personal note I`d sooner nail my b*llocks to the floor than use Kwik Fit (up).
Why, Cav? Based on Price, Quality of Service or Quality of Parts ?

I have found here for the GTi that they were half the price for a front pipe than from National = £75 saving. In fact they did a previous offer on the back box + intermediate box and squiggly pipes for £60 all in!

So far, so good!
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Post by ellevie » Sun Apr 02, 2006 1:29 pm

Thanks everybody for your feedback. If I can't get it out fairly easily then I will leave it for the MOT which is due farily soon.
David

BX19TRS 118K E Reg 1992-2008
BX19TRS auto abs 96k F Reg
BX19TXD 150k K Reg

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Post by ellevie » Wed Apr 05, 2006 6:48 pm

Exhaust sorted !
The back box was so rotten that I was able to get it away on its own and use the pipe like a handle to wiggle and hammer the other end out of the middle box with lots of WD40. The clamp on the middle box was in very good condition and I was able to reuse it. Parts and fire putty about £24.50 Not a huge saving, but a nice sense of satisfaction.

Thanks everybody for your help !
David

BX19TRS 118K E Reg 1992-2008
BX19TRS auto abs 96k F Reg
BX19TXD 150k K Reg

Stewart (oily!)
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Post by Stewart (oily!) » Wed Apr 05, 2006 6:56 pm

Another DIY triumph, and a few bob saved to boot :) well done that man.
Stewart
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Xantia Td estate, going soft