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Model specific boards => Golf mk2 => Topic started by: emery1990 on 29 August 2010, 20:43

Title: Loosing a silencer ?
Post by: emery1990 on 29 August 2010, 20:43
Ive noticed that the silencer on my downpipe/ first silencer has got a bit of rust on it in the corner, i proded it and it made a hole, im debating whether getting a stainless copy of my downpipe done, if i was to loose this silencer would it be alot louder? As i wasnt planning on doing anything with the downpipe id want to keep costs down, or are the silencers cheap anyway?
Title: Re: Loosing a silencer ?
Post by: Diamond Hell on 29 August 2010, 20:49
It'll be fine - replace with a section of tube.  It might boom a little from time to time, but if it gets too much step up to a replacement box.
Title: Re: Loosing a silencer ?
Post by: emery1990 on 30 August 2010, 10:39
Agh ok good, cheers.
Title: Re: Loosing a silencer ?
Post by: emery1990 on 30 August 2010, 21:03
I know danny_p answered my question about using an arc welder on the car, but is it  physically impossible to use an arc welder on cars? Just needs to weld in the piece tube myself instead of paying someone to do it which to them may only take half an hour or something, or should be best to hire a mig welder for a few hours.

Also what thickness is the piping ?
Title: Re: Loosing a silencer ?
Post by: Ben Lessani on 30 August 2010, 22:32
I know danny_p answered my question about using an arc welder on the car, but is it  physically impossible to use an arc welder on cars? Just needs to weld in the piece tube myself instead of paying someone to do it which to them may only take half an hour or something, or should be best to hire a mig welder for a few hours.

Also what thickness is the piping ?

Eh? As long as your car is metal and not fibreglass, I can't see why you would have any problem using an arc welder.

MIG is usually more suitable that's all, you might find Arc will blow through pretty easily (depending on your competence)

Exhaust pipe is usually about 1.5 mm thick (18/16 gauge).
Title: Re: Loosing a silencer ?
Post by: Diamond Hell on 31 August 2010, 15:35
Expect holes unless you're REALLY good with arc.  :grin:
Title: Re: Loosing a silencer ?
Post by: emery1990 on 31 August 2010, 17:08
Thats prob why he didnt recommend using the arc welder! Guessing pipe doesnt costs alot, surely a meter cant cost more than a couple of quid? then ill just buy a couple of meters to see if i can get the jist of it, if not then ill go mig, gunna be tricky though as it goes into the silencer with two pipes then out with one so im going to have to have a chop about anyway.!
Title: Re: Loosing a silencer ?
Post by: Ben Lessani on 31 August 2010, 18:40
I got a 2m length of tin a while back for £4 IIRC. The surface rust after 1 month was crazy, but it lasted me the year I ran it until I swapped to stainless.

I managed to repair a metal water pipe with arc a while back - so it is possible on thin metal, you just have to be pretty delicate - you can't let a pool build up properly, you have to build it up over and over - its slow and tedious, looks crap, but will work.
Title: Re: Loosing a silencer ?
Post by: emery1990 on 31 August 2010, 18:47
Ok cheers mate, ill give it a try with an arc welder then, is the "tin" actual tin lol or is that what the exhaust are actually made of? you can protect it though cant you with high temp paints? bit on a budget atm while i repairs it.!
Title: Re: Loosing a silencer ?
Post by: Ben Lessani on 31 August 2010, 22:13
I'm pretty sure normal exhausts are made of mild steel.

And yeah, it was actual tin ...

(http://img408.imageshack.us/img408/1863/minicimg3503jg1.jpg)
Title: Re: Loosing a silencer ?
Post by: russ-vdub on 02 September 2010, 13:03
Make sure you disconnect the battery at both ends or it could cause damage to the electrics. My mechanic puts some fancy thing across the battery when welding on it but can't for the life of me remember what its called.
Title: Re: Loosing a silencer ?
Post by: russ-vdub on 02 September 2010, 13:06
Surge protector i think..

Quote
I have used a surge protector and so far have had no trouble, but sometimes if working on site and don’t have one I have disconnected the battery or alternator. I have also just gone ahead and welded the machine without taking any precautions and to press I have been lucky, I know it’s not ideal.

There is some feeling that the surge protectors are not really up to protecting all modern sophisticated electrical systems and you should not rely on them and the only sure way is to remove any ECU's/computers completely.

I think the harm can be done when you strike the arc and remove the arc and with the surge of EMF being created and then rapidly falling off this can play havoc with the electrics.

We have been taking about this issue at work and it is one of those things that the more you think about the more worried you get, because when doing the work on someone else's car or machine what started as a quick repair could potentially cost you a lot of money. There is quite a lot on this forum site below.
http://www.ukwelder.com/forum/index.php?showtopic=6629
Title: Re: Loosing a silencer ?
Post by: emery1990 on 02 September 2010, 18:51
Thanks for that mate, ill make sure i disconnect it!.