Weber CO2 emissions MOT failure

[pedro]

I really need some help on this one please.
My 2 litre Aircooled T25 recently failed the MOT on excessive CO2 emissions. Now I really need the van up and running by the 17th July for the Latitude festival.
Right..
They are twin choke Weber IDF 40's
As I remember it, when the carbs were being fitted last year, there were a few problems. They were meant to have:
28mm chokes
F11 emulsion tubes
55 Idle jets
115 main jets.
The chokes wouldn't fit (my carbs are Italian not the newer copies). So the unstamped ones were left in. I don't know the size.
We used the F11 and the 55's. He left the main jets in and I can't for the life of me remember what they were.
At the test, the CO2 levels were 6.19.

My questions are:
What do I need to do to pass the test?
Is it something I (an absolute novice) could do?
Is there anyone in the West London, Surrey, Middlesex area who could (or know of someone) help me out. I'll be more than happy to pay.
As I say I really stuck here.

[Grun]

pedro,

Perhaps these guys could help, should be near you.

Southern Carburetters and Injection - Carburettor Reconditioning and parts sales with tuning workshop.

Unit 6,
Nelson Trading Estate,
Wimbledon,
SW19 3BL,
Great Britain,
Tel: 020 8540 2723
Email: southerncarbs@talk21.com

I found them from this site.

http://www.classic-car-directory.com

Mike

[pedro]

Cheers Mike.
I'll give them a go.

[Grun]

pedro,

I have found some formulae in 'The Aircooled VW Engine Interchange Manual' that may be of help. These are for one choke per cylinder installations.

Carb size = square root of cc per cylinder X max rpm divided by 40

Choke diameter= Carb size X 40 divided by 50

Main jet = Choke diameter X 4

If I have got it right this would give a choke size of 32
Main jet size of 128 for your IDF 40s.

These are only 'ball park' figures

Has the van passed any MOT inspection since the Webers were fitted?

Mike

[pedro]

Cheers Mike.
I'll make a note of that and hopefully have a delve about in the back later. I'm calling up a few places to see if I can get it up on a rolling road.

[pedro]

Off to Southern Carbs, in a couple of weeks. The guy there seems pretty helpful.

[Grun]

pedro,

Fella that lives opposite me here in the sticks, used to live in London and has had dealings with Southern Carbs....... speaks highly of them. 'twas a few years ago of course so hope things have not changed.

Mike

[pedro]

I spoke to him this afternoon. He seems like a good guy and very "old school" in his approach. He's confident of sorting me out without too much hassle.
Cheers for the heads up Mike.

[moloko]

get her/him/it nice and warm/ give damn good thrashing/up a stiff gradient in a lowish gear. replace airfilter/plugs/oil/filter.repeat warm up/thrashing and behold a MOT virtual cert.or if you have time a nice long run , to wherever,just get it good and warm and make it work,do not be afraid it's it's job.Remember hard work BLAH,BLAH,BLAH

[pedro]

Well, it passed the test this morning. After a good fettling at Southern Carbs, have been incredibly helpful . It's driving really well now, and I'll soon be ready for the camping and festival season. Cheers for the help and advice everyone .

[Grun]

pedro,

Thanks for the feedback, glad you are sorted.....enjoy.

Mike

[Simon Baxter]

Your van would not fail the MOT of CO2 (Carbon Dioxide) being too high, you need CO2 as high as possible, around 14% for an engine in good fettle.
You may however mean CO (Carbon monoxide) wich needs to be as low as possible.

have a read

[pedro]

You may however mean CO (Carbon monoxide) wich needs to be as low as possible.

Yeah sorry about that Simon. I did correct myself on the Brickyard tech forum. I was just having a few disengaged brain moments .