MOT emissions fail

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Surely if emissions are that bad, testing is pointless? Almost certainly smoking, start by fixing the obviously bad stuff first, you don't need an MOT sheet for that
 
kermit_rr said:
Surely if emissions are that bad, testing is pointless? Almost certainly smoking, start by fixing the obviously bad stuff first, you don't need an MOT sheet for that
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I've no idea, Im trying the easy stuff first, injector cleaning fluid, oil & filters change, accelerator adjustment etc and will see how the free re-test goes.
If still a fail, what might be the likely remedy? Fuel pump tweak?
 
LeadFarmer said:
I've no idea, Im trying the easy stuff first, injector cleaning fluid, oil & filters change, accelerator adjustment etc and will see how the free re-test goes.
If still a fail, what might be the likely remedy? Fuel pump tweak?
Click to expand...

You can detweak the fuel pump settings, wind the main fuel screw out to far and it will struggle to idle, any turns/adjustments you do make doubly sure to measure turns and measure screw length, otherwise you will spend weeks messing around to get it back to how it was before, not that I have done this before you understand, cough cough.

Thirty yrs ago, this is what we did to get the old trucks through the mot smoke test, you had no power at all, but you also had zero smoke, pass certificate in hand, back to workshop and reset pump!
 
lynall said:
You can detweak the fuel pump settings, wind the main fuel screw out to far and it will struggle to idle, any turns/adjustments you do make doubly sure to measure turns and measure screw length, otherwise you will spend weeks messing around to get it back to how it was before, not that I have done this before you understand, cough cough.

Thirty yrs ago, this is what we did to get the old trucks through the mot smoke test, you had no power at all, but you also had zero smoke, pass certificate in hand, back to workshop and reset pump!
Click to expand...

I had the fuel pump tweaked years ago to give a bit better performance, maybe as its been stood a while I need to return it to its original setting for the MOT. They guy who did it showed me how it was done, but as it was years ago I have forgotten. I recall removing a cap and then doing minor turns to an offset conical shaped thingy.
I shall search for a youtube video to refer to.
 
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LeadFarmer said:
I had the fuel pump tweaked years ago to give a bit better performance, maybe as its been stood a while I need to return it to its original setting for the MOT. They guy who did it showed me how it was done, but as it was years ago I have forgotten. I recall removing a cap and then doing minor turns to an offset conical shaped thingy.
I shall search for a youtube video to refer to.
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Rough rule of thumb is 90 clockwise on the diagphragm and the same for the max fuel screw, for more power and not to much smoke, so if you knock them both back the same?

The problem is the old tdis are dirty bags of crap, people say their exhaust smoke is clean/clear, but it it not, and it cannot be on such old tech, then we all tweak them up for a bit more go, which = more smoke, there is simply no way around it.

If you were local, I would do it for you, literally 2 minutes work.
 
Put it in 2nd or 3rd and take it to the limiter and keep it there for 20 seconds.

Worked on my works 110..

clear it's throat, 'tis an old diesel after all.
 
lynall said:
Rough rule of thumb is 90 clockwise on the diagphragm and the same for the max fuel screw, for more power and not to much smoke, so if you knock them both back the same?

If you were local, I would do it for you, literally 2 minutes work.
Click to expand...

Thanks for the info, any chance of a photo of the parts that need adjusting please? Searched YouTube but didn’t find it. I’ll try some more.
 
goonarmy said:
Is it actually Smokey?
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Not so much now, only when initially flooring the accelerator pedal.
Changed the oil & filter today. I’ll do the fuel filter on Monday when I’m back from my wet caravanning weekend in Harrogate, then take it for drive and give it some wellie.
 
Well the re-test is tomorrow morning and I will give it another hard drive before hand.

So far I have done the following..

1) Added Millers Ecomax injector cleaner to a tank of BP Ultimate diesel.
2) Changed the oil and filter
3) Changed the fuel filter
4) Changed the air filter
5) Given it some decent drives, flooring the accellerator.
6) For the test tomorrow i've adjusted the bolt that goes through the accelerator pedal, giving it 7 x full turns inwards so it now restricts the pedal from being pressed down as far as it did (I'll undo it again after the test.

Can't think of anything else I can reasonably do for now?
 
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LeadFarmer said:
It scored 2.8, against a pass mark of 3.0
I shall keep it in more regular use, for its been mostly sat on the drive for the last few months. I took it from that state straight to the MOT station which is 2 mins from my house, so no wonder it failed.
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2.8 is ferkin terrible!

Just checked my smoke tests last 4 years
1.7
1.3
1.8
0.85 (detweaked pump to below std tune as was touch and go previous year)

1993 200, tweaked pump. done 1k in the last 5 years!
 
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