Technical Exhaust hole, intermediate silencer, next step?

[Col Max Pyatnitski]

OK, I have read various threads on other people with (extra) hole(s) in their exhaust system, but still would appreciate a pointer on best way to approach this.

Thought for a while that there was a hole in exhaust: little fluttery noise from time to time somewhere under back seat. Decided to leave it as NCT (MOT equivalent) was coming up soon. Brought it for NCT and happy to say that on all the mechanicals the car passed but they couldn't test emissions due to hole in the exhaust.

I investigated further, and isolated the hole (assuming there's just one). It's at the weld where the tube attaches to the middle silencer, on the underside, and a couple of mm by a few mm in size.

From threads on forum, I'm a little unclear whether that middle silencer is needed, or what to replace with. Also unclear whether this is a good candidate for a DIY job. It'd be the first time I lay down under the car if I did do it. Not even sure how best to support car (2 axle stands at back and lift rear? or 2 at front and back on side of the exhaust? Don't have 4 stands). And would actually be properly scared going under the car (though I guess it's unlikely to be fatal since all 4 wheels would be attached?). Is it a part I'd get from motor-factors?

Or should I just go to garage? There's an independent guy who's been recommended to me who I'm going to give a call tomorrow to see about a quote now that I have a (provisional) diagnosis.

Any comments welcome!
(BTW, 2000 Fiat Punto 1.2 8v petrol)

 

[fingers99]

I'd replace like with like.

While a temporary repair is possible (probably) to give it any real chance you'll need to remove the exhaust for welding, so may as well just replace.

2 axle stands should be fine -- just place them so as to give you good, safe, access.

 

[s and b]

nice to see only posters who understand cars have posted on this one
you seem unsure Col so my strong advice would be let someone with a ramp do this for a few reasons
your health and safety
your hairline
time
problems when system wont split
car falling off ramps/axle stands
its really not worth it even though i always like to encourage home diy

 

[Col Max Pyatnitski]

nice to see only posters who understand cars have posted on this one
you seem unsure Col so my strong advice would be let someone with a ramp do this for a few reasons
your health and safety
your hairline
time
problems when system wont split
car falling off ramps/axle stands
its really not worth it even though i always like to encourage home diy

Just when I was leaning towards trying it myself!
Was looking through larger local motor-factors online store and they had a handy enough listing of all the components of the exhaust line, and I was considering buying a full setup from pipe-flange down, which would cost me about €100. Figured if I had fresh clamps and other material for the entire length then I would be less vulnerable to problems with the old bits turning out to be corroded/seized, and wouldn't need to get in there ever again in all likelihood.

I'll do a bit of phoning around today, for quotes for the work and availability of the parts, and see where I go. The bad weather forecast for the weekend might even be the deciding factor as I'll be doing this work outdoors. (would like to stick with DIY, have done all own maintenance since last NCT, including brake pads/disks replacement, plugs, leads, 2 oil changes, air/oil filters, alternator belt, and it's been a good experience! thanks FiatForum!).

One Question: when you say "system won't split" what do you mean?

 

[portland_bill]

Firstly, to everyone, never work under any vehicle unless someone else is nearby to get help if needed. A long time ago, someone I was at school with was working under his car when it slipped off the jack. It was on its wheels, so didn't squash him, just put a tiny bruise on his chest. However he was trapped and no help arrived for over 30 minutes. He died of "Shock"

One Question: when you say "system won't split" what do you mean?

All the joints will be rusted together and resist being separated. Lots of swearing to be done, and lots of rust particles in your eyes if not protected. Professionals have pipe cutters for a quick removal, which is why large outlets will always recommend full system replacement. Quicker, easier and cheaper overall. Single pieces require lots more time so will not be fitted free. Lying underneath with a hacksaw with limited movement is a horrid task.

 

[PuntoHowTo]

I did a video covering the rear section replacement a month or two back



essentially to replace the middle section isn't a huge amount more work took me about an hour-hour and a half to do this (slowed down by filming)

i always found car ramps easier to use when doing exhausts but i don't have a set anymore, however with a proper set of axle stands and chocked wheels you should have too many problems

Essentially a grinder is your friend when it comes to exhaust work cutting pipes a part and removing very rusted bolts, however they can be pretty dangerous especially if you're not used to using them and even i nearly came unstuck when i was making the above video

I posted the results of that up as a warning for others to be careful when


if you do decided to tackle it at the week end there will be plenty of people on the forum to give advice should you get stuck

 

[Col Max Pyatnitski]

Cheers Andy,
it was actually your video that made me think it might be worth trying as a DIY job (I was going to link to your cutting-disk vid in fact... though a hacksaw is slow at least it's generally in control!).

Looking at the parts-list to do a full system, there's a couple of major parts (exhaust pipe, rear silencer) and then a collection of smaller pieces (fasteners, clamps, seals) which are a couple of euro each. Working on the assumption that whatever is in the system now is 14 years old and probably very corroded/dirty and won't release easily, I'd be inclined to buy the full parts list and assume nothing gets reused. What would my shopping list look like?

Is it reasonable to expect not to need to change the rubber suspending fixtures?

Also, is there anything in particular to look for when buying ramps? is number of rungs significant?

 

[oldhammer]

Idont trust working under punto's with axle stands..
I once got pinned under rear beam on one..

If working with axle stands..I'd put a couple of wheels under too just as a fall back
Sills may get crushed if axle stands slip..but it will save your self getting crushed..

 

[KRaikkonenNo1]

I did a video covering the rear section replacement a month or two back

https://www.youtube.com/watch?v=pkctWU6s5ag

essentially to replace the middle section isn't a huge amount more work took me about an hour-hour and a half to do this (slowed down by filming)

i always found car ramps easier to use when doing exhausts but i don't have a set anymore, however with a proper set of axle stands and chocked wheels you should have too many problems

Essentially a grinder is your friend when it comes to exhaust work cutting pipes a part and removing very rusted bolts, however they can be pretty dangerous especially if you're not used to using them and even i nearly came unstuck when i was making the above video

I posted the results of that up as a warning for others to be careful when
https://www.youtube.com/watch?v=SbBVCsBtOYE

if you do decided to tackle it at the week end there will be plenty of people on the forum to give advice should you get stuck

Exactly this, I changed my whole exhaust month back or so with 3-4 axle stands,

Essentially the only problems I encountered were separating the middle and back, purchased a grinder and it was much easier,

I didn't have to worry about rubber mounts as I cut through them all and replaced them all,

Just ensure that there are always at least 2/3 axle stands supporting the car, I also keep the jack under slight pressure somewhere safe aswell (for extra security).

Finally I used one axle stand to hold the exhaust while I was moving/wiggling/removing it.

I'd give it a 5/10 difficulty wise for the confident diy'er,

Always tho safety first when getting under these (axles, jack, chocks, in gear, place tyres under raised areas)

 

[Col Max Pyatnitski]

So, on the safety element: if I do decide to DIY this job I'm going to buy ramps and do it that way (back wheels on ramps, axle stands (belt and braces) to catch car if ramp collapses, car in gear, handbrake applied, chocks under front wheels).

Still considering options:

• Rang Advance Pitstop, was quoted €125-175 for middle section depending on whether it is replaced with straight-through or middle-box (hope back box still good)
• Rang motor factors, quoted €120 for centre pipe, back box, clamp, gasket (assume rubber hangers ok), Bosal aftermarket.
• Rang Fiat parts and was quoted €322 and €288 for back box and middle box, parts only, add VAT to that. No labour in those prices. With those economics, a hole in the exhaust would write the car off!

Fiat guy was saying that there could be problems depending on whether the flexi was part of the Cat or not, and was sort of casting a lot of doubt around the process. Thought flexi would be part of the cat.

From diagrams it would look to me that if I replace the whole system, I don't need to do cutting really, or not precision cutting. The two fasteners are the clamp between back-box and centre-pipe, and then the flange between the flexi (which will be new and come on the centre pipe) and the flange at the end of the manifold/cat.

I'm still puzzled by this centre-pipe/middle-box thing.

 

[oldhammer]

Sporting models and 16valver engines..is fitted with middle box.
8valve puntos is no middle box

You don't have to cut exhausts to split them there is a easier way...
Iwouidnt pay them crazy prices for exhaust parts...

 

[Col Max Pyatnitski]

Sporting models and 16valver engines..is fitted with middle box.
8valve puntos is no middle box

Thing is, what I have is an 8V 1.2 Punto mk2 (from year '00), and it has a middle box fitted. Granted, I bought it used about 4 years ago, so anything could have happened in the 10 years before I got the car, and the chap from Advance (sort of like Kwikfit) said people might have fitted middle box just because they had one handy (e.g. from scrap).

You don't have to cut exhausts to split them there is a easier way...
Iwouidnt pay them crazy prices for exhaust parts...

Definitely won't pay the Fiat crazy prices, but the factors' price isn't too bad is it? €55 for centre pipe, 60 for back box, and a couple of yoyos for clamp and gasket (less than GBP£100 for the lot).

 

[fingers99]

Not that terrible, but I'd expect to pay less from an exhaust supplier or an eBay supplier.

 

[s and b]

just a word of warning fore anyone interested
there seems to be a consensus of opinion that using a grinder whilst upside down on your back is a good idea
well as one poster with his video has shown it is a very dangerous idea and i can assure you its not a tool i would be using (i use an airchissel)
whats failed to be mentioned is these hot sparks go everywhere and i mean everywhere so have any of you considered what impact they might have on the plastic fuel tank whilst your all busy with your earmuffs full visor and leather gauntlets on?
thought not

this is why i said let garage do it
did i mention axle stands and puntos are not a match in heaven as been mentioned,i wont go under a punto unless i leave 2 sturdy garage trolley jacks under there too and even then im woe to get down and under
finally ramps probably wont clear rear bumper as you try to drive backwards up them

by the way those prices you have been quoted lean on scandalous

might be cheaper to book a ferry to blighty and let a garage do job over here and you get a holiday

 

[Ziggy122]

i have done an exhaust on a punto without ramps - i parked it with wheels one side on a kerb and the other off

Sure its tight - but i got it done in 2hrs

but if your ever unsure about your abilities, consult help, somebody who's done it before, or works on cars more

If you were near - i'd do it for you

Ziggy

 

[oldhammer]

the way isplit them if there rusted is on is get an old screwdriver and hammer,
tap at the split parts, until they open up abeit,
then grab back box and twist it off,

Angle grinders is for the brave on low sitting cars, seen one chap once with gash on his face off angle grinder, no guard and no handle on it using it one handed in awkward areas is just a bad gamble,

ive yet to try out one of the cutters you run off air compressor,(aldi)

 

[PuntoHowTo]

Angle grinders is for the brave on low sitting cars, seen one chap once with gash on his face off angle grinder, no guard and no handle on it using it one handed in awkward areas is just a bad gamble,

ive yet to try out one of the cutters you run off air compressor,(aldi)

they can cause nasty injuries but then so can lawn mowers (people still walk around their garden with a high speed metal blade spinning inches from their flip flop protected feet)

air tools are all well and good if you have a compressor powerful enough to run them which most home hobbiest sized units aren't

as for "there seems to be a consensus of opinion that using a grinder whilst upside down on your back is a good idea well as one poster with his video has shown it is a very dangerous idea"

if you watch the video you'll see i'm not on my back in the instance of the video if i were it would have been safer as the grinder would have kicked up and away from me, i was laying on my front so when it did kick back it came up and towards me, thats all irrelevant anyway the point in the video is to demonstrate that not supporting the rear of the pipe can cause it to pinch the cutting disc, lesson learnt, don't do what i did and be safe

a grinder is no more or less dangerous than any other tool if not used properly they do have the ability to cause a lot of damage so proper PPE is needed
but don't lay on your back because its very difficult to maintain control and try to support the weight above you, it is a very bad idea

 

[GrandeGuy]

I did my nephews exhaust by finding a really high curb out of the way drove up it with the two passenger wheels on it, 0% chance of it falling off or dropping, just have to slide under the car.
Also hack saw if harder graft but safer, no sparks unless your really fast

 

[flisko]

no need to weld it andy?

 

[ChrisUK]

You'd really struggle to do any damage to the fuel tank with grinder sparks..