Technical Exhaust

[AnthonyH]

The exhaust on my Grande Punto has a leak in the flexi-pipe. I got the car up on stands today to take a look, its not the biggest leak you can imagine but enough to sound blowy and let out some fumes.

I tried to disconnect the exhaust at the down pipe under the engine and of course it wouldn't move. The previous mechanic has put what looks like black silicone selant on the nuts and they've also corroded to smitherines, so I can't get a 12mm socket on there. The bolt takes a T50 torx bit and started rounding off on its first attempted turn. So i'm at the common starting point for any job...nuts and bolts that won't budge.

I'm currently musing what to do. Any thoughts welcome.








(I have a second thread about an unresolved exhaust gasket problem I have, its a different car so not related to this).

 

[Greasytrucker]

If accessible from either side grind the heads off the bolts and knock them through and replace with new bolts. You might even be able to chisel the heads off if you have a nice sharp one. Normal practice for a rusted on exhaust tbh

 

[AnthonyH]

I just tried the angle grinder out for clearance etc, but didn't turn it on. I could get one bolt head off, but the sump would block me getting the second off. I could possibly take the handle off the grinder and this might help.

I've seen some electric saws that might work, but i don't currently have one of those.

 

[Greasytrucker]

I just tried the angle grinder out for clearance etc, but didn't turn it on. I could get one bolt head off, but the sump would block me getting the second off. I could possibly take the handle off the grinder and this might help.

I've seen some electric saws that might work, but i don't currently have one of those.

You mean the stupid handle that normally spends more time off than on! The guard on mine probably spends 50% off as well. Just be mindful of the sparks if you have to resort to this though. Bit of patience and you’ll get there

 

[AnthonyH]

You mean the stupid handle that normally spends more time off than on!

I thought it was just my brand that did that lol. I tried with the handle off and there's still not enough clearance.

The guard on mine probably spends 50% off as well. Just be mindful of the sparks if you have to resort to this though. Bit of patience and you’ll get there

I'm going to test it with the guard off next.

I have safety glasses and would need a bit more protection, and to get the car higher up on the jacks.

 

[Greasytrucker]

If you get the one ground off that you can get to and knock the bolt through you might even be able to to twist it round a bit with one bolt in to give you a bit more clearance. Trial and error really, hopefully not too much error

 

[AnthonyH]

I took the safety guard off and still not enough clearance. I could easily spend a fortnight on this, slicing the exhaust into ever smaller slivers lol

Its a big angle grinder, i could look at getting smaller grinding wheels.

 

[Greasytrucker]

The joys of home mechanics! It’s one of those where you’ve got to either A. Find a way round the problem, or B. Pay someone to do it for you. Just need to put your thinking cap on

 

[AnthonyH]

I'm currently looking at buying a 3 inch angle grinder, the one i have at the moment is 4.5 inch. One like this;

Or maybe a saw like this;

Any idea which would be best?

The reason i'm thinking about buying a tool, is that i can well imagine myself fighting with this for ages, and its kind of cold out there lol

 

[Greasytrucker]

If you think the small grinder will get in then at least you know it’ll do the job. Never used one of the small saws so can’t comment on the suitability

 

[AnthonyH]

If you think the small grinder will get in then at least you know it’ll do the job. Never used one of the small saws so can’t comment on the suitability

The 3 inch grinder would probably work, but there's a chance it could be sent back.

I'll look on youtube to see how these reciprocating saws work, you'd think it'd be like a jigsaw, but i like my battery operated cordless tools, so that'll need to be a factor.

 

[AnthonyH]

I got under there earlier and can see that I don't need a new tool, if i cut the exhaust off entirely it'll then give me enough room to get the second bolt head off.

I've decided to leave it for now though. It is blowing but i was more perturbed by the misfiring noise, the burbling noise and the tinny noise. None of which i'd noticed before. Its like the car is talking to me in its own special language, it says "fix me, i'm broken and sell me now before i blow up" lol.

Next job i should do is change the plugs and clean the MAP sensor.

 

[PuntoHowTo]

Can you get a drill into the centre of the bolt and drill it out all the way through.

You don't need to worry about any captive nuts just replace with a normal nut when you replace the pipe.

 

[AnthonyH]

I've never had any luck with drilling, i think it is meant to take ages, but then i'm probably using the wrong bits etc. so i can't practically make any headway with it.

Anyway, i'm going to delay the exhaust replacement until it gets worse or fails an MOT.

The engine has started making some slightly unusual noises which make me wonder if the cars days are numbered. Its hard to tell, but i could replace the exhaust and not long after something drastic happens lol. I won't care really, its my project car and the skills i've learnt will carry forward to the next car.

I've left the car up on stands so I can have a listen again tomorrow. I should try the screwdriver on the ear and car part procedure and see if that makes the noises become clearer or louder. Or could you suggest some other technique to track down noises?

 

[PuntoHowTo]

Boron Drill Bits go through anything.

sounds like you would just be chasing repairs and sometimes you have to just call it a day.

 

[Bartoosh]

It's a shame the blow is on the flexi pipe otherwise you could've sealed the hole with metal epoxy putty. I added a Dremel mini grinder to my toolset for those small and awkward jobs where a standard grinder simply won't do. It's proven invaluable for a host of jobs around the house as well as the car. An impact nut and bolt extractor is also another useful tool to have in your collection. Soak the offending bolt with penetrating fluid overnight and then apply heat with a blowtorch to expand the metal. There's nothing more frustrating than tackling what you perceive to be a straightforward job only to waste hours trying to remove a stubborn nut or bolt.

 

[AnthonyH]

It's a shame the blow is on the flexi pipe otherwise you could've sealed the hole with metal epoxy putty. I added a Dremel mini grinder to my toolset for those small and awkward jobs where a standard grinder simply won't do. It's proven invaluable for a host of jobs around the house as well as the car. An impact nut and bolt extractor is also another useful tool to have in your collection. Soak the offending bolt with penetrating fluid overnight and then apply heat with a blowtorch to expand the metal. There's nothing more frustrating than tackling what you perceive to be a straightforward job only to waste hours trying to remove a stubborn nut or bolt.

The extractor set is a good idea, i've been meaning to buy a kit and try them out, will see!

I have a dremmel with cutting discs but couldn't get them to make much headway on bolts, i mostly use the dremmel on my toenails lol

The strut mounts on my other car, an EVO, have started dinging, hmmm, never a moments peace with puntos....

I think i already have Boron drill bits, maybe the drill i have isn't up to it, not sure.

 

[Bartoosh]

The extractor set is a good idea, i've been meaning to buy a kit and try them out, will see!

I have a dremmel with cutting discs but couldn't get them to make much headway on bolts, i mostly use the dremmel on my toenails lol

The strut mounts on my other car, an EVO, have started dinging, hmmm, never a moments peace with puntos....

I think i already have Boron drill bits, maybe the drill i have isn't up to it, not sure.

The extractor sets are relatively inexpensive and well worth having. I learnt the hard way having wasted hours trying to tease out rusted or threaded bolts.

If you're using the dremmel on your toenails I hope you give them a polish once you're done cutting!

 

[The Panda Nut]

I just tried the angle grinder out for clearance etc, but didn't turn it on. I could get one bolt head off, but the sump would block me getting the second off. I could possibly take the handle off the grinder and this might help.

I've seen some electric saws that might work, but i don't currently have one of those.

I find Dremel really useful for some of these tasks. Aldi / Lidl do Dreemel substitutes for really good money. You often need a pile of the tiny cutting discs but its never failed me yet.

 

[AnthonyH]

The extractor sets are relatively inexpensive and well worth having. I learnt the hard way having wasted hours trying to tease out rusted or threaded bolts.

If you're using the dremmel on your toenails I hope you give them a polish once you're done cutting!

I bought these ones;

https://www.amazon.co.uk/gp/product/B07L98YYKF/ref=ox_sc_act_title_3?smid=A2Z8LB56LT9FM4&psc=1

At that sort of price i don't need to think about it for long, but I did and chose a brand that i trust. I'm looking forward to seeing if I can remove a few very rusted nuts i've left in place.

I've taken on board your advice about polishing my toenails lol. They'll soon be spick and span! lol

I find Dremel really useful for some of these tasks. Aldi / Lidl do Dreemel substitutes for really good money. You often need a pile of the tiny cutting discs but its never failed me yet.

Its interesting you say this, because I bought a few dozen discs but when they disintegrated after a few minutes i thought they can't do any big jobs. But looking at it now i should just factor in losing loads of these and it might get a job done. I'll keep this in mind now. The worst case scenario is that i get rid of the discs, which just sit around in a drawer