Technical Exhaust split from flange - repair or replace?

[fiat500]

All fitted and tightened up in the right order (though it was a hell of a job to get the top halves of the brackets on...) A quick run out to check and all seems good . I'll leave it to cool down and check the nuts/bolts (new deep brass ones for the exhaust to elbow joints).

btw, looking closely at the broken bracket, I could see that it had been welded previously... also the non-broken bracket had a weld on it, so I replaced both with new ones. It looks like the old ones had both given way at some time in the past, so well worth the peace of mind to replace them!

A neat and thorough job.

 

[Toshi 975]

A neat and thorough job.

And Halfords Advanced tools too

 

[troger]

Hi @Noah500,
you've chosen good quality.
But you know that the exhaust pipes have to be stress-relieved? (I don't know the exact term in English - in German it's called: spannunfrei glühen)
Do it with both pipes.
If not, you will quickly get the same result as with your old exhaust.
Greez
roger

 

[Noah500]

Hi Roger - I've never heard of that for exhausts before. I did tighten everything up bit by bit...

 

[troger]

Yes, but then the pipes are under a lot of tension and the exhaust breaks just like your old one.
You can see that the material is still good. Why would it be broken?
Try it out!

 

[fiat500]

Hi Roger - I've never heard of that for exhausts before. I did tighten everything up bit by bit...

I have heard of this before. I have one exhaust in my collection that has clearly been though this process. But in that case I think it was mainly to bend a 500 exhaust to fit a 600 engine...done before I got the engine.

It would certainly help to do this if retrofitting an exhaust when the elbows were not being disturbed. There is also the nagging doubt that modern exhausts may not be as accurately dimensioned as genuine Fiat parts; so maybe this helps.

Your exhaust will be fine; just keep an eye on the nuts and bolts to make sure they don't come loose.

 

[troger]

Everyone as he likes.
The website of a major german dealer (Axel Gerstl) also clearly points this out.
"Important information:
Watch Out! Exhaust systems are welded parts. Due to warpage during manufacturing, friction may occur in the exhaust pipes after installation - the consequences are cracks or breaks in exhaust pipes and welds. To avoid this, all exhaust systems for Fiat 500 and Fiat 126 should be annealed to get tension-free after installation! There is no warranty on cracks or breaks on exhaust pipes or weld seams!"
Link

 

[the hobbler]

Everyone as he likes.
The website of a major german dealer (Axel Gerstl) also clearly points this out.
"Important information:
Watch Out! Exhaust systems are welded parts. Due to warpage during manufacturing, friction may occur in the exhaust pipes after installation - the consequences are cracks or breaks in exhaust pipes and welds. To avoid this, all exhaust systems for Fiat 500 and Fiat 126 should be annealed to get tension-free after installation! There is no warranty on cracks or breaks on exhaust pipes or weld seams!"
Link

I have had a 'single outlet sports exhaust" on the (well enhanced) 650 '126 engine in my 500 for close to 11 years---never had a single break or problem with it. However, I will concede that it is probably a tad 'throatier' than it was initially.

 

[porta]

Everyone as he likes.
The website of a major german dealer (Axel Gerstl) also clearly points this out.
"Important information:
Watch Out! Exhaust systems are welded parts. Due to warpage during manufacturing, friction may occur in the exhaust pipes after installation - the consequences are cracks or breaks in exhaust pipes and welds. To avoid this, all exhaust systems for Fiat 500 and Fiat 126 should be annealed to get tension-free after installation! There is no warranty on cracks or breaks on exhaust pipes or weld seams!"
Link

I know wehn I had to get a spurious exhaust for my Prisma Symbol it ‘fitted where it touched’ rather than fitted. The workshop manager came out and did exactly this to ‘relax’ all the bends, flange and mounting points before we tightened it up to the car.
He was an ‘old hand’ that said it was common practice, where he served his apprenticeship at the GPO vehicle maintenance garage in Leeds, working on Bedford and Vauxhall vans!

 

[fiat500]

Everyone as he likes.
The website of a major german dealer (Axel Gerstl) also clearly points this out.
"Important information:
Watch Out! Exhaust systems are welded parts. Due to warpage during manufacturing, friction may occur in the exhaust pipes after installation - the consequences are cracks or breaks in exhaust pipes and welds. To avoid this, all exhaust systems for Fiat 500 and Fiat 126 should be annealed to get tension-free after installation! There is no warranty on cracks or breaks on exhaust pipes or weld seams!"
Link

Welcome @troger You are right. But we are mostly amateur mechanics, and some people here are very new to old cars. Not many owners have the sort of equipment that can heat pipes to the right temperature. The next best thing is to follow the original instructions carefully. Although some cars suffer cracked exhausts, most of us are OK.

 

[lazylobster]

Always thougt the exhaust had to be "annealed" when fitting and this would stop the stress fractures.

past tense: annealed; past participle: annealed

1. 1.
   heat (metal or glass) and allow it to cool slowly, in order to remove internal stresses and make it easier to work.