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Hi all and a happy new year to all

I removed all six plugs on my 72 and all six were black,the car had been driven a bit prior to winter strip down for painting but not a lot.My question is how difficult is it to do a basic tune if this should be needed and bearing in mind I come somewhere between zero and zero on the idiot amateur scale but I am willing to learn.I should mention 

 

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Sorry,pressed the wrong button (see what I mean about idiot)what I was about to finish with was that all plugs and leads cap,points and condenser are new and the car seemed to be running ok last year but covered approximately fifty miles when testing other components fitted

as all ways any comments gratefully received 

nige

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Is it a pi, if so how did you turn the engine off? Because the pi idles rich it nees to be ran at a couple of thousand rpm for a little while then killed without idling. The  you can get a proper look at the plugs.

 

 

 

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As do a suck test on the MU, pipe from the manifold to the MU, to check if the diaphragm is holding vacuum, as this will control the amount of richness.

The vacuum will bring the MU fueling to a better running value.

John

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Hi Nigel,

as you are going to do work on the car that will take some time I would  suggest that you do no touch the fuel system until ready for blast off in the Summer.

Then you can spend some decent time assessing the problem.

Firstly fit new plugs and then as suggested above turn the engine off in the correct way to assess the colour.

As a self professed numpty (in the nicest way) do not go fiddling with the PI controls.  Speak to a knowledgeable club member  or take to a suitable garage.

Look over their shoulder if they allow to see what is going on.

 

Roger

 

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There is also the throttle bodies to look at, such as they should all be in sync and throttle plates/ butterflies shut at idle. Plus any vacuum leaks around them. The mixture is changed via the amount of vacuum the engine is making so wear and tear or wrongly adjusted tappets can also affect it. 

Gareth

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12 hours ago, nigelcurry said:

Sorry,pressed the wrong button (see what I mean about idiot)what I was about to finish with was that all plugs and leads cap,points and condenser are new and the car seemed to be running ok last year but covered approximately fifty miles when testing other components fitted

as all ways any comments gratefully received 

nige

I suggest that just covering 50 miles before putting away May contribute to the sooting. 
I’d replace the plugs and give it a real blast to clear it’s lungs - otherwise know as an Italian tune up. Then work from there. 

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15 hours ago, Mike C said:

I'd start by looking at the fuel enrichment lever on the side of the MU and make sure it is free and  not stuck on full choke.

I suspect this is the problem. With little use the enrichment lever gets sticky. My car had had very little usage in the years before I bought it. The lever would sometimes stick on and could only be released by putting your fingers down between the engine block and metering unit to physically push the lever home. Push hard.

Soak the mechanism in WD40 or similar and move it back and forwards until it feels it is moving freely.

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19 hours ago, John McCormack said:

I suspect this is the problem. With little use the enrichment lever gets sticky. My car had had very little usage in the years before I bought it. The lever would sometimes stick on and could only be released by putting your fingers down between the engine block and metering unit to physically push the lever home. Push hard.

Soak the mechanism in WD40 or similar and move it back and forwards until it feels it is moving freely.

Then take your car out for a spirited 'Italian tune up' for at least 20 miles and check the plugs again. They will probably be fine but if not, further investigation will be required.

Nigel

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