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Smokin', Spittin' XK140

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JIM NEWMAN

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Just fired the beauty up after sitting for 6 months. Eventually ran great but at first not just a little black smoke coming out the back but gobs of soot and even black liquid dripping from the tailpipes. I've heard of rich but this was wild. I assume I have a problem with the starter carb, but what. Where do I start first? Any advice would be appreciated.
thanks
jim
 
Starter Carb would be a good bet (Had a similar problem once on my 120). BUT...since it was sitting for a long time, it could just be that your carbs need to be cleaned out. When gas sits for a long time it can really gum things up. Make sure the pistons in the carbs move freely and that they are not sticking from a gummed up needle. Just a few thoughts.

If you do figure it out for certain, be sure to post the resolution here for the benefit of others. I'm sure others will have other ideas.

Basil
 
Hello Jim,
there is not much to go wrong with the starter carburettor, it is just a simple needle with a little air valve opened or shut with the solenoid. The sensor that switches it in and out (located in the inlet manifold water rail near to the thermostat) can be unreliable. The needle has an adjustable stop to set the mixture, down to weaken and up to richen. It runs with a very loud hiss so if your black smoke occurs when hot and you can't hear that hiss then it is unlikely that the starter carburettor is at fault.
Gummed up piston(s)could be the problem as Basil suggests or that one or both carburettors are flooding. Another problem I have encountered with HD6's is that the spring that controls the jet level corrodes and lets the jet drop.
In that situation the mixture adjusting screw has no effect as the spring does not push the jet up to the adjuster.
Unfortunately it is necessary to remove the carburettors to check this. The spring is in the base of the carburettor where the float chamber bolts to the main body.

good luck,

Alec /ubbthreads/images/graemlins/thirsty.gif
 
[ QUOTE ]
gobs of soot and even black liquid dripping from the tailpipes.
jim

[/ QUOTE ]
The liquid is likely just condensed water vapor. One of the combustion by products is water. When things get warmed up the water is vaporized & you don't see it. The normal soot in the exhaust system breaks loose after sitting for a while & gets blown out. It may be running rich but probably not disastrously so.
D
 
Hello Dave,

I notice that you have mentioned this in other posts; one of the bits of useless? trivia that I remember is that 10 pints of water is produced from 1 gallon of petrol.

Alec /ubbthreads/images/graemlins/thirsty.gif
 
Hi Alec,
Very interesting. I have never bothered to do the reaction equations. I guess this must mean that 8 pints of petrol weighing 6.5 pounds, react with about 100 pounds of air to produce 10 pints of water weighing 10 pounds. (USA units) Chemical reactions are truly amazing.
D
 
Jim,
How old was the fuel and what type was it. Friend of mine had the same problem with his S-type (the real one!). He found it was the premium (i.e. high octane) unleaded petrol. Fresh fuel solved his problem. What happened to that nice leaded petrol we had before the war (to misquote the Goons)?
Graham
 
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