MoT testing Emissions '81 mgb - first psot

[jms700]

hello

just looking for some advice for my b's mot.

going in some time next week and i have a few jobs to do on it including wiper motor and hand brake adjustment. but was also wondering if any one had any tips for the emissions test? just to improve my odds?

or any recomendad stations in scotland near stirling.

thanks

[na]

Jim you could also try asking at http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgb...

must also say that normally there's a few on here very helpful and knowledgeable

if your new to, or coming back to, MGB and/or classics I can post my usually advice - I've very little mechanical knowledge but plenty of experience

Edited by na on Saturday 2nd April 22:29

[na]

whoops just noticed you're post isn't in PH's MG forum so try there also - http://www.pistonheads.com/gassing/forum.asp?h=0&a...

and hello welcome to PH

edited for spelling

Edited by na on Saturday 2nd April 22:39

[slomax]

It is just a visual smoke check on an '81. So long as it doesn't fill the garage with smoke then it should be okay. Ideally it should run so that you cannot see the exhaust gasses in reasonable temp. I have mine a little rich so there is a small amount of White smoke on acceleration. If you find you are smoking a bit too much for your liking turn the mix a little leaner by 1/16th turns at a time on the carb. You shouldn't have any running problems unless you do it too far, but you can always to back to the previous settings if you do. ( just keep a note of what you change and by how much)

eta- should probably say I do not have an MGB. A little smoke is fine, I just got an advisory for mine smoking a bit, but I also got them for having no windscreen, wipers, or washers too. Stupid.

Edited by slomax on Sunday 3rd April 02:41

[mcford]

It's not a visual smoke test, it's measured at idle for at least 5 seconds with the maximum limits of 4.5% CO and 1200 PPM Hydrocarbons.

[davepoth]

So if you want to cheat, drive to just around the corner from the MOT centre, pop the bonnet, lean out the carbs until it's running badly, drive to the MOT centre, get it tested, and then reset the mixture when just round the corner.

[slomax]

mcford said:

It's not a visual smoke test, it's measured at idle for at least 5 seconds with the maximum limits of 4.5% CO and 1200 PPM Hydrocarbons.

Really?
Mine is an '81 and im fairly sure my MOT guy said it only requires a visual... hmm....I'm not complaining!

[davepoth]

I think the change was about 1975, I have dolomites and I think the early ones are visual but the later ones aren't. The computer should have told him what to do really.