Section : Carburettors

MOT and emissions testing

Posted By : Debbie Lewis, 23-Jul-2007, 08:10pm

Hi can anyone tell me the situation with our classic cars and emission tests on the MOT. Various things I have heard and read range from, they are exempt the emissions test, to they have a not so strict test procedure.

Can anyone tell me what exactly the correct interpretation of classic cars and emissions test rules are please...

Thanks
Debbie

Followups :

MOT and emissions testing

Posted By : Charles Bushell, 23-Jul-2007, 08:16pm

Pinched from another web site:

First used before 1/8/1975 - Visual test only. Failure for excess idle speed, dense blue or black smoke for 5 seconds at idle or during acceleration up to 2500rpm or half engine max speed whichever lowest.
First used between 1/8/75 and 31/7/86 - meter test CO <=4.5%, HC<=1200ppm.
First used between 1/8/86 and 31/7/92 - meter test CO<=3.5%, HC<=1200ppm.
First used between 1/8/92 and 31/7/94 - advanced emission test (CAT) if its running on petrol when presented, to the vehicle specific limits usually around CO<=0.3%, HC<=200ppm and Lambda 0.97 - 1.03. Remember from 1st August 2001 a basic emission test will be carried out initially
- MOT and emissions testing
  
  Posted By : Debbie Lewis, 23-Jul-2007, 08:21pm
  
  Thanks for that, I've looked everywhere for some info today... I had my spitfire 1500 MOT'd and it failed the emission test, so they "tweaked" the mixture to make it run more lean to pass the test. The guy suggested I get the carbs tuned again, which is more expense... Quite a few people commented that our engines will always fail emissions test and that they were exempt etc... I just wasnt sure what was correct.
  
  Thanks
  - MOT and emissions testing
    
    Posted By : Jon Morton, 23-Jul-2007, 08:40pm
    
    It is good advice to get the car looked at. But its certainly not true that it should fail the emission. In good working order it would pass easily. Other benifits could be better fuel economy, a quicker turn of speed and better longevity for the engine.
  - MOT and emissions testing
    
    Posted By : Charles Bushell, 23-Jul-2007, 08:45pm
    
    Even the MOT testers don't always seem to know the rules. Mine was tested at the last MOT even though its an early 1975 1500. He passed it (despite high HC!) so I just said thank you. Its a good idea to get it tuned anyway for good performance & economy, you'll save money in petrol!