Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: amba on 29 June 2019, 15:35:03

Title: Rattling Cat
Post by: amba on 29 June 2019, 15:35:03
Traced the rattle from underside on tickover to the "brick"inside the offside cat.

When thumped definite loose " brick" …..other than making the nasty rattle does this have any other detrimental effect.Also on original cats had both rear lamba sensors repositioned to avoid error codes.Can I assume with a new cat I wont need the lambas moved and its just a remove and replace.

Finally any good sources for something half decent other than the usual pattern rubbish out there.

Thanks  :y
Title: Re: Rattling Cat
Post by: Enceladus on 29 June 2019, 15:58:12
If it shifts when driving it can block the exhaust and you will experience sudden loss of power. Also the cat breakup might be down to a misfire in the corresponding cylinder bank.

I doubt if an original cat is available anywhere new. And if it is it will cost more than your car is worth. So buy the cheapest third party you can find, they seem to be circa £180 each on ebay, which is significantly dearer then they were 12 months ago. You also need a fitting kit to connect to the manifold. Check ebay Germany as well.

I would post a 'wanted' in the 'bits for sale & wanted' section.

Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 16:16:22
Cheers for guidance.

No misfire and runs like a swiss watch but recently noticed the "rattle".

Remember replacing both on my old MFL Elite and if memory serves me they were around £100 each so seems they have jumped up.

Will get onto sourcing replacement...does the fitting kit you mention just mean the gasket and stud nuts ?
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 29 June 2019, 16:48:23
Yes, whenever a the Death Rattle has appeared I have replaced the cats.

The last ones I obtained were from Sutton Auto Factors for £177 inc. VAT each in 2015.  They do not appear to now stock them!! ::) ::)

But that is a price guide for what have proved to be good replacements that I had my VX main dealer fit. ;)
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 16:56:56
Thanks Lizzie.

Found ideal replacement from Germany at £215 with £20 delivery then another £15 for the fitting bits.

Will do it myself but another £250 ontop of the £450 paid last week for 4 new tyres and "the spend goes on"...Trouble is what the option other than replacing but with what.Had a looked at a nice Black  Merc C320 AMG but its tractor fuelled and not as comfy as the Omega . :-[
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 29 June 2019, 17:06:03
Thanks Lizzie.

Found ideal replacement from Germany at £215 with £20 delivery then another £15 for the fitting bits.

Will do it myself but another £250 ontop of the £450 paid last week for 4 new tyres and "the spend goes on"...Trouble is what the option other than replacing but with what.Had a looked at a nice Black  Merc C320 AMG but its tractor fuelled and not as comfy as the Omega . :-[

 ;D ;D ;D ;D  I have just posted Omega Ownership Costs under General Car Chat that touches on all that amba! :D :D ;)
Title: Re: Rattling Cat
Post by: dave the builder on 29 June 2019, 17:22:09
£167 on ebay plus about £10 for a fitting kit
or have a cat welded in
or maybe a used one as per your wanted post
Title: Re: Rattling Cat
Post by: Enceladus on 29 June 2019, 17:26:28
I've never changed a cat on a 3.2, only 2.5 & 3.0. I believe for fitting you will need the gasket at the manifold end. Two of the distorted thread all metal lock nuts, they're M10 I think. I seem to recall that they're made of copper. Ideally fit two new studs, if they come out easily. Else leave them alone or they might shear off.

At the other end since it's new it should have pre-threaded drillings in the flange to accept set-screws inserted from the middle section flange. The middle section flange is not threaded. Else use a suitable length nut and bolt with spring washers. The usual issue with separating the middle sections from the cats is that the set-screws shear in the cat flanges and you have to drill out the broken bits. Pain in the backside if the cat is still on the car, a simple job suddenly gets difficult. You won't have that issue, but I suppose you could consider drilling out the threads on the cat flange before you fit it. That way you won't have trouble if you later want to renew the exhaust.

Some of the members use some Loctite (or similar) high-temp sealer joining the middle section to the cat.

£235 delivered sounds a bit steep to me. Is it an original or an aftermarket?
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 17:28:29
Several options thanks Dave. :y

Resigned myself to spending £200 + so will see what gives me the better option  :)
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 17:33:41
173917331145..off fleabay but from Germany..fitting kit extra so around £250 all in.

Yes remember the 2.5 MFL the studs stayed put so just fitted new gasket and copper M10 nuts.

When exhaust center section last changed fitted stainless nuts and bolts so hopefully will split ok ..last hopeful words ;D
Title: Re: Rattling Cat
Post by: dave the builder on 29 June 2019, 17:41:43
173917331145..off fleabay but from Germany..fitting kit extra so around £250 all in.

Yes remember the 2.5 MFL the studs stayed put so just fitted new gasket and copper M10 nuts.

When exhaust center section last changed fitted stainless nuts and bolts so hopefully will split ok ..last hopeful words ;D

CAREFUL "driver side" in Germany is passenger side on a UK car with the  driver sitting in the correct seat  ;D  :y

Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 17:51:21
Opps ...silly me  :D
Title: Re: Rattling Cat
Post by: Alnico Blue on 29 June 2019, 17:54:29
Off side  rattling on my 2.6 as well  Andrew  . .
but only does it after at least 8 hours standing (overnight really) :D

As it stops within about 30secs to a minute  as the cat warms  & then don't hear it anymore until next morning  . . .I  have learned to live with it   :D :D

Decided that with this car,  I have had it coming up for 3 years now   . . . it cost £300 . .so I am just gonna run it until it falls apart. just doing usual oil changes , brakes etc.   NOT even gonna do another cam belt on it . . .lets see how long it will really last  :D :D :D  So  cannot see me spending £200 +  on a new cat  :y :y
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 18:04:46
See your logic Al.

I use my car everyday for work and most days drive over 100 miles and have done so for years.Everything works as it should and its a real pleasure to drive,albeit I am now starting to get the dreaded rust spots showing on the rear arches.

My reasoning is it earns me a living and replacing it now for something on par is going to cost 7-8k even assuming I can tolerate it.

I can live with the rattling tbh it s just I hoped for an inexpensive fix tbh and £200 seems about right as its only 3 tanks of fuel...tyres are essential consumables so I live with that running cost as its tax deductible.

Will see if I can find a good SH first off the forum then go from there
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 29 June 2019, 18:13:53
I've never changed a cat on a 3.2, only 2.5 & 3.0. I believe for fitting you will need the gasket at the manifold end. Two of the distorted thread all metal lock nuts, they're M10 I think. I seem to recall that they're made of copper. Ideally fit two new studs, if they come out easily. Else leave them alone or they might shear off.

At the other end since it's new it should have pre-threaded drillings in the flange to accept set-screws inserted from the middle section flange. The middle section flange is not threaded. Else use a suitable length nut and bolt with spring washers. The usual issue with separating the middle sections from the cats is that the set-screws shear in the cat flanges and you have to drill out the broken bits. Pain in the backside if the cat is still on the car, a simple job suddenly gets difficult. You won't have that issue, but I suppose you could consider drilling out the threads on the cat flange before you fit it. That way you won't have trouble if you later want to renew the exhaust.

Some of the members use some Loctite (or similar) high-temp sealer joining the middle section to the cat.

£235 delivered sounds a bit steep to me. Is it an original or an aftermarket?

My VX dealer needed 2 x Gaskets at £7.80
                               4 x Screws at   £10.20
                               4 x Screws at   £1.92

How they used them I have not a clue!! ::) ::) ;D ;D ;)

All I know is that including the cats they purchased on my behalf from the supplier I recommended, plus labour, it cost a total of £556.90 for the two to be fitted;)
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 18:22:25
That's quite a Pelican ,Lizzie but at £200+ per cat I see how they got there .

I will fit it so just need a sensible price for the parts :)
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 29 June 2019, 18:40:01
That's quite a Pelican ,Lizzie but at £200+ per cat I see how they got there .

I will fit it so just need a sensible price for the parts :)

But the way I calculate it is a write down, on a 5 year depreciation scale, of just £111.38 per year, which is in the acceptable zone for running a car ;)
Title: Re: Rattling Cat
Post by: STEMO on 29 June 2019, 18:43:28
That's quite a Pelican ,Lizzie but at £200+ per cat I see how they got there .

I will fit it so just need a sensible price for the parts :)
Big bill...I geddit.
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 18:49:18
Dead right..Stemo
Title: Re: Rattling Cat
Post by: Migv6 le Frog Fan on 29 June 2019, 18:51:26
If I were you I would consider taking the opportunity to source and fit a pair of 2.5/ 3.0 cats, which removes the issues associated with 2.6/ 3.2 cats. I would expect to pay around £120 for the pair.
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 18:55:31
Albs...what does that do to the fueling and where does the other lamba wiring go ?
Title: Re: Rattling Cat
Post by: STEMO on 29 June 2019, 18:57:16
If I were you I would consider taking the opportunity to source and fit a pair of 2.5/ 3.0 cats, which removes the issues associated with 2.6/ 3.2 cats. I would expect to pay around £120 for the pair.
That is a very good idea. :y
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 19:04:28
That was my initial thought but curious where the 2nd lamba goes ( no rude comments please !!! ) and  is the wiring for the 1st lamba long enough ,assuming that the one that gets fitted 
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 29 June 2019, 19:10:04
If I were you I would consider taking the opportunity to source and fit a pair of 2.5/ 3.0 cats, which removes the issues associated with 2.6/ 3.2 cats. I would expect to pay around £120 for the pair.
That is a very good idea. :y

Yes, but I have to ask the question, if a pair of 2.5/ 3.0 cats do the same job why did Vx fit the 2.6 / 3.2 ones if it does not interfere with performance? ??? ???
Title: Re: Rattling Cat
Post by: Nick W on 29 June 2019, 19:25:01
If I were you I would consider taking the opportunity to source and fit a pair of 2.5/ 3.0 cats, which removes the issues associated with 2.6/ 3.2 cats. I would expect to pay around £120 for the pair.
That is a very good idea. :y

Yes, but I have to ask the question, if a pair of 2.5/ 3.0 cats do the same job why did Vx fit the 2.6 / 3.2 ones if it does not interfere with performance? ??? ???




They have an extra cat in the downpipe to bring the emissions back in line with the earlier higher compression engines.


I used THESE  (https://www.ebay.co.uk/itm/Fits-Vauxhall-Omega-2-5-V6-Genuine-BM-Cats-Exhaust-Manifold-Catalytic-Converter/292661536418?fits=Car+Make%3AVauxhall%7CModel%3AOmega&hash=item4423fca6a2:g:wmsAAOSwjYdbX0Vq)on my car for five years with no issues. Andrew would need another lambda boss welded on to use them on his car. That's another £10(absolute maximum) and a few minutes eay work to do as it's not on the car. Saves more than £100 per side. I would not pay £50 for 8 standard metric fasteners while there is still a hole in my arse!


I don't believe in using secondhand exhaust components(other than reliable manifolds), even if they are free.

Title: Re: Rattling Cat
Post by: Migv6 le Frog Fan on 29 June 2019, 19:45:20
As above really. The later ones are a bit of a bodge and don't work very well. Hence the emissions light coming on all the time.
I believe the old style cats were also better quality as they were always easy to sell for good money to scrappys etc.
The later have a lot less scrap or resale value.
As for the lamda question - It s so long since Ive seen the underneath of a 2.5/ 3.0 I cant remember how many lamdas they have.  :-[ ;D
It sounds like its only two instead of four though ?
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 20:05:58
So just to be crystal clear on this.

You can buy and fit std 2.5/3.0 cats as per Nicks post and images.You then get a friendly man with welding skills to cut and fit a second lamba boss into the new cat.

Fit the new cat and connect up to 2 existing lamba per side and jobs jobbed ...no lights or issues and only slight downside is the cats are as good as the OEM that are being replaced.

For £120 for 2 cats..bit of the welding and the bosses and good to go ...is that it in a nut shell then ?

Fancy an earner Nick ? :y
Title: Re: Rattling Cat
Post by: biggriffin on 29 June 2019, 21:49:01
I'm with Nick, buy a pair of 3.0L downpipes, get a pair of bosses from eBay, get them welded in (there's a guide) cut 3mm off the new pipes, and fit, use some M12 nuts n spring washers,x4, drill out both flanges, exhaust end and fit m8x55, nuts bolts washers,  off you jolly we'll go.
Title: Re: Rattling Cat
Post by: amba on 29 June 2019, 23:05:19
Thanks for clarification .BG.

Think I will need to have a chat with Mr.Nick  ;)
Title: Re: Rattling Cat
Post by: Alnico Blue on 30 June 2019, 09:31:50
I'm with Nick, buy a pair of 3.0L downpipes, get a pair of bosses from eBay, get them welded in (there's a guide) cut 3mm off the new pipes, and fit, use some M12 nuts n spring washers,x4, drill out both flanges, exhaust end and fit m8x55, nuts bolts washers,  off you jolly we'll go.

Trev    So for that cost I may well do this  . . .But Cut 3mm off new pipes where from , why / what for etc.  :-\ :-\     have i missed not read something or  can you advise?   :y :y :y
Title: Re: Rattling Cat
Post by: Migv6 le Frog Fan on 30 June 2019, 09:44:15
The 2.5 / 3.0 downpipes don't quite fit onto the 2.6/ 3.2 fanimolds without a bit of a trim.  :y
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 10:11:55
Blimey, after reading all that you have to do, all the hassle, to fit 2.5 / 3.0 cats and not the larger I would just fit the standard ones right for the car.  ::) ::) ::)

I know, a simple point of view from a female!! ;D ;D ;D ;)
Title: Re: Rattling Cat
Post by: biggriffin on 30 June 2019, 10:39:14
I'm with Nick, buy a pair of 3.0L downpipes, get a pair of bosses from eBay, get them welded in (there's a guide) cut 3mm off the new pipes, and fit, use some M12 nuts n spring washers,x4, drill out both flanges, exhaust end and fit m8x55, nuts bolts washers,  off you jolly we'll go.

Trev    So for that cost I may well do this  . . .But Cut 3mm off new pipes where from , why / what for etc.  :-\ :-\     have i missed not read something or  can you advise?   :y :y :y


You cut the 3mm from the end that goes into the manifold, when you put a 3.2 alongside a3.0 downpipe all is self explanatory.
Title: Re: Rattling Cat
Post by: Nick W on 30 June 2019, 10:46:00
Blimey, after reading all that you have to do, all the hassle, to fit 2.5 / 3.0 cats and not the larger I would just fit the standard ones right for the car.  ::) ::) ::)

I know, a simple point of view from a female!! ;D ;D ;D ;)


you trim 3mm off the pipe that goes into the exhaust manifold - a couple of minutes careful work with an angle grinder. That's the only thing that stops you bolting the earlier cat in place, everything else is the same.


Drilling a hole for, and welding the additional lambda boss(which is the fix for a stock 3.2 cat anyway) takes less time than getting out the tools to do it. A quick look on Ebay returned bosses at £2 each.


So, perhaps 10minutes of simple work saves about £130 per side. And eliminates a common fault in the process. Why wouldn't you do it?


Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 10:51:11
Blimey, after reading all that you have to do, all the hassle, to fit 2.5 / 3.0 cats and not the larger I would just fit the standard ones right for the car.  ::) ::) ::)

I know, a simple point of view from a female!! ;D ;D ;D ;)


you trim 3mm off the pipe that goes into the exhaust manifold - a couple of minutes careful work with an angle grinder. That's the only thing that stops you bolting the earlier cat in place, everything else is the same.


Drilling a hole for, and welding the additional lambda boss(which is the fix for a stock 3.2 cat anyway) takes less time than getting out the tools to do it. A quick look on Ebay returned bosses at £2 each.


So, perhaps 10minutes of simple work saves about £130 per side. And eliminates a common fault in the process. Why wouldn't you do it?

Ok, thanks :D :D :y
Title: Re: Rattling Cat
Post by: Raeturbo on 30 June 2019, 11:00:03
One of mine is rattling too, so my plan is to get it on the ramp and gut the two of them and see what happens before I go any further. I will report what trouble I inevitably will get into but that’s happening first ;D
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 11:13:46
Blimey, after reading all that you have to do, all the hassle, to fit 2.5 / 3.0 cats and not the larger I would just fit the standard ones right for the car.  ::) ::) ::)

I know, a simple point of view from a female!! ;D ;D ;D ;)


you trim 3mm off the pipe that goes into the exhaust manifold - a couple of minutes careful work with an angle grinder. That's the only thing that stops you bolting the earlier cat in place, everything else is the same.


Drilling a hole for, and welding the additional lambda boss(which is the fix for a stock 3.2 cat anyway) takes less time than getting out the tools to do it. A quick look on Ebay returned bosses at £2 each.


So, perhaps 10minutes of simple work saves about £130 per side. And eliminates a common fault in the process. Why wouldn't you do it?

Ok, thanks :D :D :y

.....................I would add though, are these cats for £63 actually up to the standard amba needs on his 2003 3.2 Omega?

I have read the whole page of the suggested cats by Nick W post #24 -

 https://www.ebay.co.uk/itm/Fits-Vauxhall-Omega-2-5-V6-Genuine-BM-Cats-Exhaust-Manifold-Catalytic-Converter/292661536418?fits=Car+Make%3AVauxhall%7CModel%3AOmega&hash=item4423fca6a2:g:wmsAAOSwjYdbX0Vq

 I note the following warning, and these cats are NOT Type Approved, which may give you problems come the MOT?_

If your vehicle is registered before 1st March 2001, then you DO NOT need to fit a Type Approved Catalytic Converter. However, if your vehicle is registered after 1st March 2001, then YOU MUST fit a Type Approved Catalytic Converter in accordance with UK Legislation Laws.


So, just to reiterate amba Omega is a 2003 3.2 ;)

 ;)
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 11:22:25
Blimey, after reading all that you have to do, all the hassle, to fit 2.5 / 3.0 cats and not the larger I would just fit the standard ones right for the car.  ::) ::) ::)

I know, a simple point of view from a female!! ;D ;D ;D ;)


you trim 3mm off the pipe that goes into the exhaust manifold - a couple of minutes careful work with an angle grinder. That's the only thing that stops you bolting the earlier cat in place, everything else is the same.


Drilling a hole for, and welding the additional lambda boss(which is the fix for a stock 3.2 cat anyway) takes less time than getting out the tools to do it. A quick look on Ebay returned bosses at £2 each.


So, perhaps 10minutes of simple work saves about £130 per side. And eliminates a common fault in the process. Why wouldn't you do it?

Ok, thanks :D :D :y

.....................I would add though, are these cats for £63 actually up to the standard amba needs on his 2003 3.2 Omega?

I have read the whole page of-

 https://www.ebay.co.uk/itm/Fits-Vauxhall-Omega-2-5-V6-Genuine-BM-Cats-Exhaust-Manifold-Catalytic-Converter/292661536418?fits=Car+Make%3AVauxhall%7CModel%3AOmega&hash=item4423fca6a2:g:wmsAAOSwjYdbX0Vq

as suggested I note the following warning, and these cats are NOT Type Approved, which may give you problems come the MOT?_

If your vehicle is registered before 1st March 2001, then you DO NOT need to fit a Type Approved Catalytic Converter. However, if your vehicle is registered after 1st March 2001, then YOU MUST fit a Type Approved Catalytic Converter in accordance with UK Legislation Laws.


 ;)

the only time anyone official will look at his car is at MOT time
the car is that old that the NT (nominated tester  ,MOT man) won't know or remember that the 3.2 or 2.6 had an extra cat section compared to the 2.5 or 3.0, he will look to see it has a cat , and will test the exhaust emissions , which the car will need to pass  :y

so having the cats warmed up before MOT is a good idea ,and fun  ;D :D
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 11:26:44
Blimey, after reading all that you have to do, all the hassle, to fit 2.5 / 3.0 cats and not the larger I would just fit the standard ones right for the car.  ::) ::) ::)

I know, a simple point of view from a female!! ;D ;D ;D ;)


you trim 3mm off the pipe that goes into the exhaust manifold - a couple of minutes careful work with an angle grinder. That's the only thing that stops you bolting the earlier cat in place, everything else is the same.


Drilling a hole for, and welding the additional lambda boss(which is the fix for a stock 3.2 cat anyway) takes less time than getting out the tools to do it. A quick look on Ebay returned bosses at £2 each.


So, perhaps 10minutes of simple work saves about £130 per side. And eliminates a common fault in the process. Why wouldn't you do it?

Ok, thanks :D :D :y

.....................I would add though, are these cats for £63 actually up to the standard amba needs on his 2003 3.2 Omega?

I have read the whole page of-

 https://www.ebay.co.uk/itm/Fits-Vauxhall-Omega-2-5-V6-Genuine-BM-Cats-Exhaust-Manifold-Catalytic-Converter/292661536418?fits=Car+Make%3AVauxhall%7CModel%3AOmega&hash=item4423fca6a2:g:wmsAAOSwjYdbX0Vq

as suggested I note the following warning, and these cats are NOT Type Approved, which may give you problems come the MOT?_

If your vehicle is registered before 1st March 2001, then you DO NOT need to fit a Type Approved Catalytic Converter. However, if your vehicle is registered after 1st March 2001, then YOU MUST fit a Type Approved Catalytic Converter in accordance with UK Legislation Laws.


 ;)

the only time anyone official will look at his car is at MOT time
the car is that old that the NT (nominated tester  ,MOT man) won't know or remember that the 3.2 or 2.6 had an extra cat section compared to the 2.5 or 3.0, he will look to see it has a cat , and will test the exhaust emissions , which the car will need to pass  :y

so having the cats warmed up before MOT is a good idea ,and fun  ;D :D

I hope you are right Dave, but it has to be a gamble with the MOT being beefed up.  After spending the money, applying a lot of time and effort to fit these sub-standard cats to amba's car he could find it failing and having to revert to plane A, involving more costs and time!

Personally I have always stuck to the legal approach to avoid future hassle :D ;)

Title: Re: Rattling Cat
Post by: Nick W on 30 June 2019, 11:33:48

the only time anyone official will look at his car is at MOT time
the car is that old that the NT (nominated tester  ,MOT man) won't know or remember that the 3.2 or 2.6 had an extra cat section compared to the 2.5 or 3.0, he will look to see it has a cat , and will test the exhaust emissions , which the car will need to pass  :y

so having the cats warmed up before MOT is a good idea ,and fun  ;D :D


Exactly.


There's a lot of rubbish talked about pattern parts in general and cats in particular. Yet thousands of businesses fit them everyday to make money - you lose money if your customer returns with a fault you could have avoided. That said, everybody has largely anecdotal evidence for why they avoid certain brands - I don't buy Denso sparkplugs on the basis of two sets that lacked durability. That's not a big enough sample to make a definitive conclusion, but avoiding them is so easy it makes more sense to do so.


I don't expect a £70 cat to last 15 years like the originals did, but then the rest of the car is unlikely to do so either. Also, my experience over the last 30 years is that no replacement part lasts as long as the original(even if genuine), which is one reason I dislike disturbing stuff unnecessarily. That brings us back to the cost/benefit/hassle/performance comparison that only you can prioritise.
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 11:48:16
I'd think the only reason they fitted 2 cats per bank was to reduce emissions further
but one well positioned,decent cat will do the job
fit 2 in one pipe and the second may never get hot enough until 30 mins of driving, which for some owners ,is the journey  ::)

as for reducing emissions , I've said before, an older car ,used for 20 years must have less "carbon footprint" than building and recycling 2 or 3 cars that have less emissions out the exhaust pipe  :-\
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 11:52:27

the only time anyone official will look at his car is at MOT time
the car is that old that the NT (nominated tester  ,MOT man) won't know or remember that the 3.2 or 2.6 had an extra cat section compared to the 2.5 or 3.0, he will look to see it has a cat , and will test the exhaust emissions , which the car will need to pass  :y

so having the cats warmed up before MOT is a good idea ,and fun  ;D :D


Exactly.


There's a lot of rubbish talked about pattern parts in general and cats in particular. Yet thousands of businesses fit them everyday to make money - you lose money if your customer returns with a fault you could have avoided. That said, everybody has largely anecdotal evidence for why they avoid certain brands - I don't buy Denso sparkplugs on the basis of two sets that lacked durability. That's not a big enough sample to make a definitive conclusion, but avoiding them is so easy it makes more sense to do so.


I don't expect a £70 cat to last 15 years like the originals did, but then the rest of the car is unlikely to do so either. Also, my experience over the last 30 years is that no replacement part lasts as long as the original(even if genuine), which is one reason I dislike disturbing stuff unnecessarily. That brings us back to the cost/benefit/hassle/performance comparison that only you can prioritise.

I didn't specifically question the life longevity of these cats, but the legal status of them.

An MOT tester on the ball will see the conversion work to make the non Type rated cats fit, and these are guys who now fail vehicles for having air fresheners on the screen, let alone fully technical issues.  If the regs say you must have a certain standard of exhaust system part fitted, and you do different, then there is a risk of failure.  You may get away with it twice out of three MOT's, but the risk is there.

That is what I was pointing out.  You get what you pay for :D ;)
Title: Re: Rattling Cat
Post by: Alnico Blue on 30 June 2019, 12:54:56
  Nick . . . .presume that you had no issues at MOT time with those replacements fitted?

Some will follow your good advice  . . .but on here there will always be someone looking into issues too deeply. 
Senario:  MOT  man will shove the sensor up the exhaust , run the programme, emissions results will come out , car passes if OK.

Is any tester gonna say you have the wrong cats fitted . . .   Several , if not more , Oofers have taken this route of fitting 3.0 cats to 3.2's and i don't recall any issues at MOT time being reported .

But . . .if these actual £63 cats don't pass the UK MOT emissions testing then of course there is problem  :-\

Lets see what Nick says about his experience at MOT time
Title: Re: Rattling Cat
Post by: Diamond Black Geezer on 30 June 2019, 13:24:21
Weren't they added from a legislation point of view for Euro IV (or whatever) I thought that whether your car is from 1996, or 2003, the emissions test on the MoT is the same parts per million/carbons etc. However, if a manufacturer wanted to make a car in 2003 to the same engine specs of a 1996 car, they wouldn't get type approval. Bit that's not the same as what you're allowed on the MoT.
Hence why dozens of FL Omega owners have fitted earlier cats and passed emissions tests every year, because euro/worldwide emissions regs and MoT test regs aren't one and the same. That's how I understood it
Title: Re: Rattling Cat
Post by: Nick W on 30 June 2019, 13:47:10
  Nick . . . .presume that you had no issues at MOT time with those replacements fitted?

Some will follow your good advice  . . .but on here there will always be someone looking into issues too deeply. 
Senario:  MOT  man will shove the sensor up the exhaust , run the programme, emissions results will come out , car passes if OK.

Is any tester gonna say you have the wrong cats fitted . . .   Several , if not more , Oofers have taken this route of fitting 3.0 cats to 3.2's and i don't recall any issues at MOT time being reported .

But . . .if these actual £63 cats don't pass the UK MOT emissions testing then of course there is problem  :-\

Lets see what Nick says about his experience at MOT time


I used them on a 3.0 which had the 3.2 manifolds fitted. So I did trim the ends to fit the manifolds, but didn't need to fit extra lambda bosses. The only difference I noticed between the new and old cats was that the new ones didn't rattle. They fit perfectly, didn't affect performance, exhaust volume/tone or affect the (very basic) MOT emissions test. And they were still doing all of that five years later when I got rid of the car.




There is nothing on the parts that say whether they're Type Approved. Once they've been on the car for a few months with heat and dirt staining, nobody is going to care.


The MOT tester is going to note the conversion work. Really? How? The trimmed pipe is inside the manifold. The extra boss might be noticeable, but the main reason for that is that the welding is likely to be prettier than the stock ones!
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 13:52:41
for MOT euro emission standards (as per VTS device/ in service exhaust emission standards for road vehicles 19th edition)
x25xe and x30xe are Max CO Limit %Vol 0.3 Fast Idle, 0.5 Normal Idle, 200 ppm HC
z26se and z32se  are Max CO Limit %Vol 0.3 Fast Idle, 0.5 Normal Idle  200 ppm HC
0.97 to 1.03 lambda obviously
x prefix being euro 2 1996 on
z prefix being euro 3 2000 on

so that was well thought out  ;D



Title: Re: Rattling Cat
Post by: Raeturbo on 30 June 2019, 13:54:06
Exactly the same then
Title: Re: Rattling Cat
Post by: Nick W on 30 June 2019, 14:01:44
And the H/C requirements are largely unaffected by the cat and O2 sensors unless there is something badly wrong upstream; it's a better view of how good the bores/pistons/rings/valve stems are.
Title: Re: Rattling Cat
Post by: biggriffin on 30 June 2019, 14:05:04
Putting 3.0L cats on a 3.2L doesn't affect the emissions for mot.
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 14:08:13
Putting 3.0L cats on a 3.2L doesn't affect the emissions for mot.

for those who wanted a plain English summary of the tech talk  :y  ;D
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 14:30:16
Fair enough everyone; I am out voted!   ::) ::) ;D ;)

I just wanted to make amba clear of the facts with the cats being advertised when he has the same model as me of the same year ;)

Better to be safe than sorry as my mum always said 8) 8) :y
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 14:58:08
Fair enough everyone; I am out voted!   ::) ::) ;D ;)

I just wanted to make amba clear of the facts with the cats being advertised when he has the same model as me of the same year ;)

Better to be safe than sorry as my mum always said 8) 8) :y
not so
you make valid points Lizzie  :)
also, we all pay £305 to spew Co into the air , because we drive polluting tanks
My emissions at MOT where zero C0 ,HC was very low (can't remember exact number)

yet I follow new cars spewing out visible smoke , they pay £30 RFL  :-\ :(
 
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 15:01:03
Fair enough everyone; I am out voted!   ::) ::) ;D ;)

I just wanted to make amba clear of the facts with the cats being advertised when he has the same model as me of the same year ;)

Better to be safe than sorry as my mum always said 8) 8) :y
not so
you make valid points Lizzie  :)
also, we all pay £305 to spew Co into the air , because we drive polluting tanks
My emissions at MOT where zero C0 ,HC was very low (can't remember exact number)

yet I follow new cars spewing out visible smoke , they pay £30 RFL  :-\ :(

Thanks Dave! :y

I was beginning to think differently given some of the reactions! ::) ::) ;)
Title: Re: Rattling Cat
Post by: amba on 30 June 2019, 17:00:28
I didn't realise I had opened up "Pandoras Box".

Logic on a cost basis is to fit the cats from a 3.0/2.5 with the single catalytic converter,although as only 1 of mine is rattling the decision has been clouded slightly tbh.

Do I buy 2 at a cost of around £150 and then pay the extra for bosses which accept is negligible but as I don't have the skill set or equipment to weld then that is an extra cost.I am therefore in effect needing to replace 2 ...of which 1 original seems to be working correctly to avoid an MOT tester noticing 1 cat has 2 catalytic boxes and the other only 1 which I assume would be a no go 
Title: Re: Rattling Cat
Post by: Doctor Gollum on 30 June 2019, 17:11:48
A bit of light reading...

https://www.gov.uk/government/publications/catalytic-convertors/catalytic-converters-advice-on-type-approval-and-legal-requirements-for-suppliers-and-manufacturers :y
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 17:47:01
A bit of light reading...

https://www.gov.uk/government/publications/catalytic-convertors/catalytic-converters-advice-on-type-approval-and-legal-requirements-for-suppliers-and-manufacturers :y

Yep, very interesting and in particular the following paragraphs should be food for thought for those intending to use a non sapproved type on a car that requires the approved cat:

"Breaching the requirements of the 2009 Regulations can amount to a criminal offence, punishable by a fine of up to £5,000.

It is also an offence under the Road Vehicles (Construction and Use) Regulations (Regulation 61a(3)) to use a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards it was designed to meet. The potential penalties for failing to comply with Regulation 61a are fines of up to £1,000 for a car or £2,500 for a light goods vehicle."


But I suppose everyone has the right to make their own decision, take the risks and then take the consequences if they arise, like with everything else we do with our cars ;)
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 17:48:41
I didn't realise I had opened up "Pandoras Box".

Logic on a cost basis is to fit the cats from a 3.0/2.5 with the single catalytic converter,although as only 1 of mine is rattling the decision has been clouded slightly tbh.

Do I buy 2 at a cost of around £150 and then pay the extra for bosses which accept is negligible but as I don't have the skill set or equipment to weld then that is an extra cost.I am therefore in effect needing to replace 2 ...of which 1 original seems to be working correctly to avoid an MOT tester noticing 1 cat has 2 catalytic boxes and the other only 1 which I assume would be a no go

I know what I would do, but it is your decision amba after considering all the above; best of luck with that! :D ;)
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 17:55:46
I didn't realise I had opened up "Pandoras Box".

Logic on a cost basis is to fit the cats from a 3.0/2.5 with the single catalytic converter,although as only 1 of mine is rattling the decision has been clouded slightly tbh.

Do I buy 2 at a cost of around £150 and then pay the extra for bosses which accept is negligible but as I don't have the skill set or equipment to weld then that is an extra cost.I am therefore in effect needing to replace 2 ...of which 1 original seems to be working correctly to avoid an MOT tester noticing 1 cat has 2 catalytic boxes and the other only 1 which I assume would be a no go

I know what I would do, but it is your decision amba after considering all the above; best of luck with that! :D ;)
Team up with someone who's cat is rattling on the other side Lizzie to reduce the cost  :-\  ;D

Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 17:57:01
I didn't realise I had opened up "Pandoras Box".

Logic on a cost basis is to fit the cats from a 3.0/2.5 with the single catalytic converter,although as only 1 of mine is rattling the decision has been clouded slightly tbh.

Do I buy 2 at a cost of around £150 and then pay the extra for bosses which accept is negligible but as I don't have the skill set or equipment to weld then that is an extra cost.I am therefore in effect needing to replace 2 ...of which 1 original seems to be working correctly to avoid an MOT tester noticing 1 cat has 2 catalytic boxes and the other only 1 which I assume would be a no go

I know what I would do, but it is your decision amba after considering all the above; best of luck with that! :D ;)
Team up with someone who's cat is rattling on the other side Lizzie to reduce the cost  :-\  ;D

 ;D ;D ;D :P
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 18:04:52
.....that famous scene in the great film Dirty Harry with Clint Eastwood comes to mind:

"Well, punk, are you feeling lucky?  Well are you?  I know what you are thinking, has my Magnum, the worlds's most powerful hand gun fired six shots, or just 5?"  :D :D ;)
Title: Re: Rattling Cat
Post by: dave the builder on 30 June 2019, 18:41:09
.....that famous scene in the great film Dirty Harry with Clint Eastwood comes to mind:

"Well, punk, are you feeling lucky?  Well are you?  I know what you are thinking, has my Magnum, the worlds's most powerful hand gun fired six shots, or just 5?"  :D :D ;)

The Department of Transport are Hiring Clint Eastwood to shot people with non type approved cats  :o
that's even more wasting My £305 a year road tax  :(
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 30 June 2019, 18:53:17
.....that famous scene in the great film Dirty Harry with Clint Eastwood comes to mind:

"Well, punk, are you feeling lucky?  Well are you?  I know what you are thinking, has my Magnum, the worlds's most powerful hand gun fired six shots, or just 5?"  :D :D ;)

The Department of Transport are Hiring Clint Eastwood to shot people with non type approved cats  :o
that's even more wasting My £305 a year road tax  :(

Well I can believe that as anything could happen in this mad world of today! ::) ::) :D ;)
Title: Re: Rattling Cat
Post by: amba on 30 June 2019, 20:58:03
Its not the issues at MOT time that concerns me as to be totally honest I expect the average MOT guy isnt even looking at the cats just if the exhaust is blowing as does the car have any terminal rot underneath or are any bushes or track arms showing movement.

The real issue I have is the cost options:

Buy a correct to fit twin lamba drilled cat specific for model...around £200 ish with onlythe effort in removing the old 1 and fitting the replacement...hopefully a sensible mornings work and all fixed.

Or buy 2 new cats at around £150 ..add the cost of the welding in the 2 bosses which I cannot do then have twice the work fitting 2 new cats with the modification of the down pipes which could go horribly wrong.

Mind made up...new cat to fit specific model along with bits to fit...will order in the morning but many many thanks for sharing various views  :y
Title: Re: Rattling Cat
Post by: Lizzie Zoom on 01 July 2019, 09:54:47
Its not the issues at MOT time that concerns me as to be totally honest I expect the average MOT guy isnt even looking at the cats just if the exhaust is blowing as does the car have any terminal rot underneath or are any bushes or track arms showing movement.

The real issue I have is the cost options:

Buy a correct to fit twin lamba drilled cat specific for model...around £200 ish with onlythe effort in removing the old 1 and fitting the replacement...hopefully a sensible mornings work and all fixed.

Or buy 2 new cats at around £150 ..add the cost of the welding in the 2 bosses which I cannot do then have twice the work fitting 2 new cats with the modification of the down pipes which could go horribly wrong.

Mind made up...new cat to fit specific model along with bits to fit...will order in the morning but many many thanks for sharing various views  :y

Good decision amba! 8) 8) :y
Title: Re: Rattling Cat
Post by: amba on 01 July 2019, 10:22:23
Hope so ,but it saves me half the work albeit a bit more expensive in the long run.

Great advise and guidance from all much appreciated
Title: Re: Rattling Cat
Post by: Enceladus on 01 July 2019, 15:02:27
If you've previously moved the downstream lambda sensor on both banks, then you might want to similarly modify the new cat before you fit it. Otherwise it will be obvious, on a ramp, that the two sides don't match.
Title: Re: Rattling Cat
Post by: amba on 01 July 2019, 16:47:45
Yes good point ...so either way I need a man with a welder !!...although I really doudt my regular MOT place would notice tbh :D
Title: Re: Rattling Cat
Post by: biggriffin on 01 July 2019, 17:31:07
Yes good point ...so either way I need a man with a welder !!...although I really doudt my regular MOT place would notice tbh :D

Yup.
Title: Re: Rattling Cat
Post by: Nick W on 01 July 2019, 17:56:18
Yes good point ...so either way I need a man with a welder !!...although I really doudt my regular MOT place would notice tbh :D


fitting a boss into new pipe off the car will take a couple of minutes.


I'll happily do it, but will need some notice as neither of my welders are here. And I'm out all weekend.
Title: Re: Rattling Cat
Post by: amba on 01 July 2019, 18:04:16
Thanks for kind offer Nick.

Will call around at somepoint if that's ok and we can sort things out .When r.u around ?..pm me would be fine  :y