MOT emissions failure

[v8turbo]

Hi Guys,
My Transit failed its MOT on emissions! Just brought it over a week ago as a project, Its running a 2.0 pinto and has a newish weber 32 34 DMTL 0 135 06 carb, the MOT tester tried to adjust the mixture as far as it would go but it was still way out! I have searched the net for info on the carb and nothing shows up with that number stamped on the carb?

[AndyG]

What exactly did it fail on (hydrocarbons, Co )
And by how much

[v8turbo]

It failed on both, CO needed to be down under 3.5 and mine is over 7.1, hydrocarbons was way high but I dont remember what! not sure if the carbs right for my engine? MOT tested turned the idle mixture as far in as it would go but could not get it to read lower? I have brought a Gunsons gastester so will have a fiddle

[AndyG]

Is the air filter clean/good

Check the colour of your spark plugs after a run
Also check that they're all firing too

[v8turbo]

air filter is good, plugs are black and sooty due to running rich, I can not take it for a good run as it has no mot.

[AndyG]

Well it does sound like either it's the wrong carb, the jets aren't correct for the application (your engine) or there's also a slight possibility that the float chamber isn't working correctly, allowing the excess fuel to just pour into the engine

I'll see if madmark has any ideas on this

[v8turbo]

took the carb off checked it all and refitted it, brought a gunsons gastester and been messing about with the idle mixture, if I wind the mixture screw in too much engine stalls, so I have turned it out as little as possible to get it to run on tickover at the leanest setting. The gastester as to be set at 2.0 and left for 10 mins, when put in the tail pipe this setting drops to 1.5 to 1.7? the gunsons manual is very sparse on infomation! any one used a gastester? looking on the floor it has a large black sooty deposit patch under the tailpipe did a search on the net and have read to put acetone in the fuel tank? or use some injector cleaner?

[mr. pitts]

V8,
it's not the choke system sticking in the on position by any chance?

[mr. pitts]

air filter is good, plugs are black and sooty due to running rich, I can not take it for a good run as it has no mot.

Black sooty plugs can also be a symptom of an ignition fault. Put a new plug in one of the leads & check what the spark is like.
On a more personal note, if you have any electrical parts made by Intermotor, throw them away, i can almost guarantee they are duff, even if new.

[v8turbo]

V8,
it's not the choke system sticking in the on position by any chance?

no checked that, have taken off the air filter and been running it off to check choke

[v8turbo]

cap and plugs look newish, and leads look ok, this setup has an ECU to run the dizzy....

[Altransit]

It's been a long time since I messed around with a carburettor, but from what I remember, with a Weber, adjusting the idle screw, does nothing for the running mixture, as that is handled by a different set of jets entirely

[hornhead]

Hi would say new plugs and oil then carb.
if you turn in mixture till its hunting then speed up idle,CO goes down.

mot tester showed mewhen i took weber in for first time...i like really relaxed tick over but you can't get low co that way..thats why vv carbed ones idle so fast,to not misfire.

now have 2 paint marks on screws,mot setting and how it should be

[AndyG]

if I wind the mixture screw in too much engine stalls, so I have turned it out as little as possible to get it to run on tickover at the leanest setting. The gastester as to be set at 2.0 and left for 10 mins, when put in the tail pipe this setting drops to 1.5 to 1.7?

Is that not OK for the MOT

And as already mentioned, turn the idle up slightly too

[v8turbo]

It's been a long time since I messed around with a carburettor, but from what I remember, with a Weber, adjusting the idle screw, does nothing for the running mixture, as that is handled by a different set of jets entirely

yes the idle mixture screw adjusts the CO (these sometimes are hidden with caps), and the fast idle screw adjusts tickover