Technical Seized exhaust back box

[AnthonyH]

My EVO's exhaust decided to break today and i've had trouble getting it off. The middle section is ok, the backbox has to be replaced. Its all off apart from the last section (pictured) that I've peeled back like a can of sardines - but it is reluctant to budge now. I've had plenty of penetrant on it. Any suggestions?

 

[jackwhoo]

I really dislike exhaust sleeve joints...
Hit the bit where one tube slides into the other with a hammer all round.
You may end up cutting a slit along one side and later using exhaust paste on the slit.

 

[bugsymike]

Yes, exactly as @jackwhoo says, with a really tight one I use two hammers, one to absorb the blow on the opposite side to the area I am hitting.
The affect is to expand the outer sleeve so that it then slides off the inner.
As long as you can work as much around the pipe as possible, I have never known it fail.
Mind you "toffee hammers and limp wrists" will not do the job, you have to show it who is boss

 

[AnthonyH]

Yes, exactly as @jackwhoo says, with a really tight one I use two hammers, one to absorb the blow on the opposite side to the area I am hitting.
The affect is to expand the outer sleeve so that it then slides off the inner.
As long as you can work as much around the pipe as possible, I have never known it fail.
Mind you "toffee hammers and limp wrists" will not do the job, you have to show it who is boss

I'll show it who's boss lol.

If I can't duff it up on the car I'll take the mid section off and wrestle it.

I really dislike exhaust sleeve joints...
Hit the bit where one tube slides into the other with a hammer all round.
You may end up cutting a slit along one side and later using exhaust paste on the slit.

Thanks for the idea. I have an angle grinder so if need be I'll cut a slit in it .

 

[bugsymike]

I'll show it who's boss lol.

If I can't duff it up on the car I'll take the mid section off and wrestle it.



Thanks for the idea. I have an angle grinder so if need be I'll cut a slit in it .

Another joke in the motortrade in the past was, in the mechanic toolbox was a hammer, screwdriver and a" french letter", if you can't fix it, "f*** it"

 

[AnthonyH]

Another joke in the motortrade in the past was, in the mechanic toolbox was a hammer, screwdriver and a" french letter", if you can't fix it "f*** it"

Lol.

Writing a reply but still laughing so I'll leave it there. I'm sure this joke is so good it's multi layered so I'll be on the look out for it now

 

[AnthonyH]

I took the mid section off and wrestled it until the backbox came off...

I then set about taking the backbox off my SORN/spares Grande Punto, thankfully it came off a lot easier.

I've cleaned up the backbox/mid-section as much as I can, getting a lot of rust off the intersection. I won't have too much trouble getting a used backbox on will I? Will grease be of any use/wise? I'm going to need a new gasket so the job will have to wait to get finished.

It feels like I've done this job twice now. Anyone ever worked in the scrap trade? Any good?

 

[bugsymike]

I took the mid section off and wrestled it until the backbox came off...

I then set about taking the backbox off my SORN/spares Grande Punto, thankfully it came off a lot easier.

I've cleaned up the backbox/mid-section as much as I can, getting a lot of rust off the intersection. I won't have too much trouble getting a used backbox on will I? Will grease be of any use/wise? I'm going to need a new gasket so the job will have to wait to get finished.

It feels like I've done this job twice now. Anyone ever worked in the scrap trade? Any good?

If it is after any catalysts etc. then if a little oil helps you get it on , it will soon burn off with the heat of combustion.
The main thing is getting a good gas tight seal at all the joints to prevent any popping on the over run, also to prevent any premature deaths by occupants due to carbon monoxide poisoning
You should be able to stop the engine with no leaks by holding a cloth over the tail pipe.

 

[AnthonyH]

If it is after any catalysts etc. then if a little oil helps you get it on , it will soon burn off with the heat of combustion.

Using oil sounds good, thanks.

The main thing is getting a good gas tight seal at all the joints to prevent any popping on the over run, also to prevent any premature deaths by occupants due to carbon monoxide poisoning

I will use new bolts on the join between the cat and mid-section, some none standard bolts and giant washers had been put on there at some point in the past and i'm waiting for a new gasket on there too. I'm somewhat tempted to also steal the mid section off my spares GP because it a lot newer but this job seems big enough already.

You should be able to stop the engine with no leaks by holding a cloth over the tail pipe.

I'll give that a go and report back when the exhaust is back on. How long do I need the cloth to be in place?

My GP and EVO are keeping me way too busy, and its not like there aren't other jobs waiting in the wings The FIAT Grande Punto designers must have had a lot of fun, what with going on holiday and taking really long breaks from their designs lol

 

[bugsymike]

I'll give that a go and report back when the exhaust is back on. How long do I need the cloth to be in place?

If it is still running after about 20 seconds , you have a leak, providing you make a good seal!

 

[AnthonyH]

I put it together and have a small leak at the join of the backbox and midsection, I was kind of expecting this but hoping it wasn't going to be the case...

I'll try to reposition the clamp tomorrow.

I stole the gasket and backbox off my spares car and it occured to me I could have used the midsection off that too. It may have been better to keep the backbox and midsection together.

Ah well. At least England won eh?