Let's say your "specific" problem is as this unfortunate chaps though.
Could be any number of things causing the problem. Partially blocked jet, incorrect float level, lack of compression, partial siezure, leaking crank seals. The mechanic systematicaly works througheach of these untill he finds eactly which one is then culprit but he can't actually charge for the time doing so? He's just supposed to be clairvoyant and just know exactly what the cause is instantly, otherwise he's useless?
I agree though that if a coked up pipe was the issue, a mechanic should have no problem recitifying it.
And you never answered my final question.
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