BM catalytic converters?

[dobbslc]

The boys Aygo needs a new cat and I've seen loads on eBay brand new for £50. I'm not sure if these are any good but have seen some by a UK based company called BM, has anyone used them and are they decent quality.
They are double the price but I really don't want anymore work or fault codes on his car!

 

[CompoSimmonite]

Bought a cheap CAT off eBay and couldn't get it to seal properly to cylinder head. Close examination showed sub standard quality so ended up returning for refund and paying considerably more for one from local supplier (think it was a BM but not 100% sure) - which fitted perfectly. I'd be very wary if a CAT seems too cheap as there will be a reason why !

 

[JOEPRO]

I have used BM cats before on Mercedes and thought they were decent quality

 

[JOEPRO]

Here you go - pics of it. I put it on my 1995 S500 C140 coupe

 

[dobbslc]

Thanks for that chaps! BM it is if the boy wants to fix his car...

 

[badabec]

Thanks for that chaps! BM it is if the boy wants to fix his car...

I expect you'll be fixing it at your expense.

 

[dobbslc]

^ if he can bugger off to Hungary and then Paris on holiday recently he can afford to fix his burluddy car!

 

[PhillipM]

I've used a few of 'em for friends and relatives on a budget, they're cheap and cheerful and might get you through the first MOT if you're lucky, and that's about it.

 

[premmington]

I've used a few of 'em for friends and relatives on a budget, they're cheap and cheerful and might get you through the first MOT if you're lucky, and that's about it.

Thats my take on it - I fitted a few ex our local motor factors.

Yeah they have cleaned the exhaust up enough for an MOT pass.

But if you wanna keep the EML off - you will be needing something better for the long game.

 

[dobbslc]

I've used a few of 'em for friends and relatives on a budget, they're cheap and cheerful and might get you through the first MOT if you're lucky, and that's about it.

I'm assuming you're talking about the cheap Ebay ones here?

 

[steveo3002]

got a bm one on the focus , id say its cr@p actual cat bit is no where as big as the original , and they must just use universal cans as the pipe diameter was squeezed down to fit to it , as above a year later it wont pass the mot

not sure what choices there is as genuine is out of the question , mine was £80 so if its that per year to get it through then so be it

 

[steveo3002]

how about this genuine one , only 130£ lol

 

[bricol]

got a bm one on the focus , id say its cr@p actual cat bit is no where as big as the original , and they must just use universal cans as the pipe diameter was squeezed down to fit to it , as above a year later it wont pass the mot

not sure what choices there is as genuine is out of the question , mine was £80 so if its that per year to get it through then so be it

I have heard of a new cat being fitted for MOT, then removed, sealed up, and a section of pipe fitted for 11 months 29 days . . .

 

[steveo3002]

I have heard of a new cat being fitted for MOT, then removed, sealed up, and a section of pipe fitted for 11 months 29 days . . .

yeah did think of that

 

[Robotstar5]

I have heard of a new cat being fitted for MOT, then removed, sealed up, and a section of pipe fitted for 11 months 29 days . . .

A friend of mine who runs a small garage (one man band) does that for one of his customers.

 

[PhillipM]

I'm assuming you're talking about the cheap Ebay ones here?

No the BM ones. But they're pretty much the same thing.

You can get 100-300 quid for the scrap metal in a lot of used cats, that should give you an idea of how much reactive material is in a brand new replacement that only costs £50 for everything...

 

[CompoSimmonite]

No the BM ones. But they're pretty much the same thing.

You can get 100-300 quid for the scrap metal in a lot of used cats, that should give you an idea of how much reactive material is in a brand new replacement that only costs £50 for everything...

I got £175 for the scrap CAT off my old Smart Fortwo.

 

[JOEPRO]

No the BM ones. But they're pretty much the same thing.

You can get 100-300 quid for the scrap metal in a lot of used cats, that should give you an idea of how much reactive material is in a brand new replacement that only costs £50 for everything...

Remember too that catylist technology has come a long way from the 80s.

Cars which used to come with large heavy and expensive cats can equally be served with smaller cats now.

Which was the case on my S500. It's cats were burned out / damaged / broke up. I couldn't get any genuine good used parts. I ended up about +£50 difference on recycling the old ones and buying the new ones. I was pleased with the fitment on the BM ones, lighter and car passed MOT no issues. Granted it only does a couple hundred miles a year so I don't think it'll wear out any time soon.

 

[PhillipM]

Not really the cat tech - we've had sophisticated 3-way cars since the 90s - that's more down to injection, mapping and things like manifold air injection.

There's a reason the BM ones are lighter, they put the bare minimum in to meet regs - and that's also the reason they had to bring in EC type approval regulations on the aftermarket catalysts a decade or so ago to force 'em to make something at least reasonable.

I've never had a BM cat make it past the second MOT after fitting - I only throw them on cars where it has to be done for the absolute lowest cost and/or they're repairing the car to get rid of it shortly.

 

[PhillipM]

A friend of mine who runs a small garage (one man band) does that for one of his customers.

I mean it works, keeps the cat fresh for the next MOT

Not that I've ever done that, officer.