help needed (pics inside)

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99sei
Joined: Sun 14 Dec, 2008 19:27
Posts: 64

  Z3 roadster 1.9
Location: Coventry

help needed (pics inside)

Post by 99sei »

After my car sounding a little tinny upon acceleration i decided to investigate.

Now im hand with a spanner but certainly not any expert so would like a little advice.

This is the cat isnt it?

Image

Now look at what i have found inside

You can just make out where the other end of the exhaust joins the other end
Image

Where the end of the torch is you can see a faint circle around it - this is where the other end of the exhaust attaches

Image


NOTHING. Isnt there meant to be baffles in here? there shouldnt be a big empty space should there?
z3Dave
Joined: Sun 20 Apr, 2008 11:52
Posts: 143

  Z3 roadster 1.9
Location: Chester

Post by z3Dave »

From the outer looks like my cat from cats2go.

Yes i think it should have a ceramic mesh in...
99sei
Joined: Sun 14 Dec, 2008 19:27
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

i thought it was meant to have baffles inside to coat the harmful gasses in something or other, but id just like someone to confirm im right or even better show me a pic of their cat
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Canman
Joined: Tue 21 Jul, 2009 15:34
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  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

Image
Image


Please help. The money will go to a good cause. email me for the link to my fundraising page.
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Gazza
Joined: Tue 04 Oct, 2005 20:58
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  M roadster S54
Location: Romford Essex

Post by Gazza »

Canman wrote:Image
:roflmao: :roflmao: :roflmao:
Gazza

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"

Z3 S54 M roadster Image, BMW Z1, BMW M3 CSL, Z4M Coupe
ImageImage
99sei
Joined: Sun 14 Dec, 2008 19:27
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

i knew someone would post a pic of their actual cat but was too lazy to type catalytic converter
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Canman
Joined: Tue 21 Jul, 2009 15:34
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  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

sorry couldn't resist. meeoow :D :D
Image


Please help. The money will go to a good cause. email me for the link to my fundraising page.
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Robert T
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Joined: Mon 12 Jun, 2006 10:35
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  Z3 roadster 1.9
Location: Cheshire

Post by Robert T »

Assuming your profile is correct, and that you have a facelift 1.8, then this is the front section:

http://www.realoem.com/bmw/showparts.do ... g=18&fg=10

The rear section joins to this with a front box and and a rear box. The cat sits forward of the join. Wonder if yours is some kind of cat bypass, as I understood it to contain some kind of honeycomb.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
Image
99sei
Joined: Sun 14 Dec, 2008 19:27
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

Thats not mine. Mine is the 1.9 and it doesnt have a lamba on it from what i can see, which is very weird unless it is on the outlet manifold

this is my car, which is believe is pre facelift?

Image
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Robert T
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  Z3 roadster 1.9
Location: Cheshire

Post by Robert T »

You have a pre-facelift 1.9 with the M44 engine - same as mine. I was going by your profile which says 1.8. :wink:

This is the front section of your exhaust:

http://www.realoem.com/bmw/showparts.do ... g=18&fg=10

Cat is still the frontmost box, with two more boxes to the rear.

The lambda probe is part #8 - ignore part #9 as it is not fitted to our cars (the diagram may well be used for another car).

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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99sei
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

profile changed :oops: anyone know what colour it is? It just says blue on the V5.


From what i can see the whole exhaust system comprises of 3 parts

Outlet manifold - down to mid section (where the cat is) - the back box

now from the pics and what you said the pic i have taken is the cat, should it have honeycomb filters in or not? anyone got a pic of theirs?

Thanks for all the advice so far
99sei
Joined: Sun 14 Dec, 2008 19:27
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

right ive just been out to have a look at the car again just to make sure ive got things right

first box from the engine to the back of the car is the cat, then the what i presume to be silencer? and then the back box.

Now the pic taken in the first photograph are of the first box where i would have expected to find honey combs.

Image
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Robert T
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  Z3 roadster 1.9
Location: Cheshire

Post by Robert T »

Your car is Atlanta Blue. :wink:

No pics of zed cats from me I'm afraid - I've not had to replace mine yet.

I did find this though:

http://www.2carpros.com/how_does_it_wor ... verter.htm

It clearly shows that the cat should be full of honeycomb/mesh type structure.

Logically the cat should be the frontmost box as it needs to be hot in order to work properly, and BMWs ETK (what we see through RealOEM) confirms that we are looking at the cat in the picture. I am still somewhat bemused as to what your cat has done with its guts. :?

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
Image
99sei
Joined: Sun 14 Dec, 2008 19:27
Posts: 64

  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

Thank you for taing the time to give me this advice.

Ive come across this once before but never on a BMW cat. The only thing i can think of is it has broken down so severly that it has blown the parts through the exhaust.

Ive been quoted £150 for a cat which isnt too bad i dont suppose, as thats only £40 fitting fee. And after looking at the rusted bolts that might be a good fee to pay :) Does anyone know where i can get a backbox from? or even a cat? im more than capable of fitting it all my self providing i can get the three bolts undone.
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Canman
Joined: Tue 21 Jul, 2009 15:34
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  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

have you had a recent mot? if so the car should have been tested for emmisions. therefore testing your CAT. maybe mine and others are the same as yours , just that we haven't looked into ours. sorry if this is a daft post but sometimes we dont always see whats in front of us and see the worst.
Image


Please help. The money will go to a good cause. email me for the link to my fundraising page.
Wessex
Joined: Sun 14 Jun, 2009 15:16
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  Z3 roadster 2.8
Location: Verwood, DorZ3t
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Post by Wessex »

Have you had the car long? It's not unheard of for the cat to be removed and a straight through fitted in order to get better breathing from the engine exhaust. Even 3lb back pressure was considered to be quite a reduction in power output at the wheels when cats began to find their way into the exhaust system in the early 80s (in this country). America had cats in the 70s and were removed when imported into this country because the lead in our petrol then (no lead free until the early 80s) ruined & clogged the cats.

The Cat would be replaced for the MOT inspection and then removed for a year before repeating the process.

The bits can't have just blown out!!! When the honeycomb collapses it justs sits there creating a further blockage.

A lot of trouble but not to a mechanically minded person with a pit in the garage or access to a lift; or can pay a mate!
99sei
Joined: Sun 14 Dec, 2008 19:27
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

Had an mot about a month ago and it passed, did have a few issues with emissions though.

Are baffles not made of a collapsable susbstance so therefor i would have thought the could be blown out.

As for the increase in power its meant to do, it sounds aweful if this is the cause of the problem (it sounding tinny under load) For a proper decat though you had to have a straight metal piece inplace for the flow of the gases?

Canman - you are thinking exaxtly what i am thinking - if it cant be blown out where has it gone? Hence why i was asking if anyone had any pics.
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Canman
Joined: Tue 21 Jul, 2009 15:34
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  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

did it fail on emissions then ?
maybe the honeycomb has fell into the cavaity of the cat box. maybe giving high or varying emission readings . which is why you cant see it.
hope you get it sorted, seen this on ebay
http://cgi.ebay.co.uk/BMW-Z3-1-9-1997-2 ... 286.c0.m14
Image


Please help. The money will go to a good cause. email me for the link to my fundraising page.
Wessex
Joined: Sun 14 Jun, 2009 15:16
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  Z3 roadster 2.8
Location: Verwood, DorZ3t
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Post by Wessex »

There is no cavity. The material inside the chamber fills the chamber. The exhaust gas passing throught the honeycomb undergoes a change through the chemical reaction once the cat has heated up.

Have you read the link that Robert posted?

http://www.2carpros.com/how_does_it_wor ... verter.htm

The pictures you want are there!

The tinniness may well be in the silencer or back box. My exhaust had a tinny rattle, especially when cold. Since I fitted the new back box, see here,

http://picasaweb.google.co.uk/Wessex121 ... J2u24nnhwE#

the tinny rattle has gone.

If and it's a big if, if the material had disintegrated to dust, and it won't because it's ceramic, then there would be a big hollow where your torch is not a tube.

Peter.
Mike Fishwick
Joined: Fri 19 Jun, 2009 10:27
Posts: 2093

  Z3 roadster 2.8
Location: Daglan, France

Catalytic Converter

Post by Mike Fishwick »

I was going to post a picture showing what a catalytic converter SHOULD look like inside, but the system will not permit another picture in this thread.

I tried to post an article and picture in the Z3 Knowledgebase, but was informed that only moderators can do so - what is going on?
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Titan
Joined: Fri 01 Apr, 2005 20:20
Posts: 4002

  Z3 roadster 2.2i
Location: North Yorkshire

Post by Titan »

Mike
I don't know about a picture limit but the knowledge base has been made "read only" because too many people were asking questions therein.
If you have a thread or subject worthy of addition, post it and ask for it to be moved into the knowledge base.
See here
Image :devil:
Wessex
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  Z3 roadster 2.8
Location: Verwood, DorZ3t
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Post by Wessex »

I don't see the problem. The thread that Robert posted and I repeated shows what a ceramic cat looks like in side the box. It is not formed in a tube. The resistance would be too great for the engine to run efficiently.

Your best bet would be to take the unit to a reputable mechanic and ask his opinion.
99sei
Joined: Sun 14 Dec, 2008 19:27
Posts: 64

  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

Ive read the links and agree with what is being said but if you look at the pic i have posted of what it looks like inside my cat, then it is hollow. nothing in there except space, no sign of anything.

Which has got me thinking how has it become empty or if i was missing something and for some reason (what ever the reason) it is meant to be like that on a Z3
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Jonttt
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  M roadster S54
Location: Liverpool

Post by Jonttt »

99 but for the fact its just past its MOT I would have said it has some sort of Decat fitted, thats why the replacement part is really just an extension of the exhaust pipe to fill the gap where the Cat would be.

I'm by no means an expert on these things but would take it to kwik fit who should have a look and advise you free of charge.
Happiness is not around the corner........happiness is the corner
Image Video or Journal Garage: 2015 FFRR Black Edition, Porsche Boxster GTS, 1997 Porsche Carrara C4S, Ex 2001 BMW S54 Z3m Roadster
99sei
Joined: Sun 14 Dec, 2008 19:27
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  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

I would never take it to quick fit - i have heard so many bad stories from there - but i will be taking it somehwere to get checked out.

I think ill order a new cat for it and keep the old one, then i can spend a bit of time on it and make it a proper de-cat.

Now have to think should i get a new backbox too and if i do, do i get a aftermarket one or standard one. £160 for universal backbox with choice of tip or £175 for a standard replacement one. decisions decisions
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Jonttt
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Post by Jonttt »

99

Kwik Fit does depend on individual ones, no doubt there are some bad ones out there but my experience has only been good.

Unless they are really busy they will usually have a look at things with you looking over their shoulders and you can always take somewhere else after to actually get it fixed.

I just called into one as I had a really bad front tyre on my work car. They happened to have one in stock and initially wanted £60 more than I knew I could get from a mobile supplier. They dropped the price to match and I got it done there and then.

I would take it to kwik fit just to get an opinion for free, nothing to lose :wink:
Happiness is not around the corner........happiness is the corner
Image Video or Journal Garage: 2015 FFRR Black Edition, Porsche Boxster GTS, 1997 Porsche Carrara C4S, Ex 2001 BMW S54 Z3m Roadster
Wessex
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  Z3 roadster 2.8
Location: Verwood, DorZ3t
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Post by Wessex »

Do let us know your findings please. I'd be very interested to know the engineers report.
99sei
Joined: Sun 14 Dec, 2008 19:27
Posts: 64

  Z3 roadster 1.9
Location: Coventry

Post by 99sei »

ill keep people posted, its much appreciated the amount of help you have all been
Wessex
Joined: Sun 14 Jun, 2009 15:16
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  Z3 roadster 2.8
Location: Verwood, DorZ3t
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Post by Wessex »

Bump!

So what was the outcome? Was it a decatted exhaust?

And did you have a new cat fitted or stayed with the setup?
Bluecar
Joined: Thu 26 Jun, 2008 11:56
Posts: 96

  Z3 roadster 1.9
Location: Weymouth

The shame of it!!!!

Post by Bluecar »

Just sharing my experience of my cat'. For about a week the car lost power and began 'hopping'. This just got worse, so booked in to my indi' on Friday for him to work on at the weekend. Drove about 1.5 miles at 20 mph and broke down. Had to be towed, the shame of it, to the garage where it was diagnosed as having a knackered cat' where the honeycomb has disintegrated and caused a blockage. Going to cost £260 for a new one. :(
Wessex
Joined: Sun 14 Jun, 2009 15:16
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  Z3 roadster 2.8
Location: Verwood, DorZ3t
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Post by Wessex »

Wessex wrote:Bump!

So what was the outcome? Was it a decatted exhaust?

And did you have a new cat fitted or stayed with the setup?
I repeat, what happened???

Peter
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