Van Failed its MOT - CO emissions - update

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Ralf85
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Van Failed its MOT - CO emissions - update

Post by Ralf85 »

I was surprised to have this result. The only but very annoying thing it failed on was item 7.3.B.1a, regarding carbon monoxide emissions.

I think that my carb has been running rich after being tweaked a few months ago. Would adjusting the carb to make it run leaner get those emissions down to a pass level?
Cheers.
Last edited by Ralf85 on 23 Jan 2018, 13:49, edited 1 time in total.

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T25Convert
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Re: Van Failed its MOT - CO emissions

Post by T25Convert »

In short, yes. High CO is normally too much fuel, not enough air. How high was high?

Assuming you have the Solex 34 Pict 5 on your DF engine still then its too brass screws on the side to adjust air-fuel volumes at idle - these chaps do a good guide for an earlier version of the carb, same principals apply: http://www.vw-resource.com/34pict3.html

Worth checking it has a clean air filter and was tested warm/hot as well.
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Ralf85
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Re: Van Failed its MOT - CO emissions

Post by Ralf85 »

Cheers buddy. That is really helpful.
:ok

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Mr Bean
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Re: Van Failed its MOT - CO emissions

Post by Mr Bean »

Maybe an old wive's tale and call me old fashioned but I always like to give the engine a bit of a thrash before I drop the van/car in for an MOT. A couple of junctions on a motorway at 70MPH on a warmed up engine seems to work for me.
CS
E D I T:
Sorry delete "thrash" and 70 MPH and insert "As quickly and safely as the vehicle in question can reasonably go" :oops:
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Ralf85
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Location: West London - 1985 westie pop top, LHD, 1900 DF engine

Van Failed its MOT - CO emissions - update

Post by Ralf85 »

I left the van with my garage yesterday to adjust the carb back to its correct set-up. The van has now passed the MOT test and been serviced. I collected it this morning in a jolly mood. :)

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