"Jack.... You don't say ho
"Jack.... You don't say how long you've owned this engine, or when it last ran properly. However, if you've owned it for a year or so, and if when you last used it, it ran properly.... and since then it has been sitting for a couple months or more, I would strongly suspect that the carburetors are clogged/fouled/gummed in such a manner that a restriction exists that is interfering with the slow speed passageways. That would result in the exact problem as you explain it.
There are "Seal Rings" on the crankshaft, seperating one cylinder from another, (a engineering design that has existed since 1958), but I have never seen one fail in any respect, other than engines that have been under water (salt water). Bottom line is, I don't buy that seal ring story!
You can check the carburetor theory by removing the carburetor face plate cover, run the engine at idle (after a warm up), then one after another, stick two fingers into the carb throats. When you hit a clogged/fouled carburetor, the engine will smooth out somewhat, and the rpms will increase (Usually more than one carb, but it could be just one).
Is there another dealership/marine mechanic in your area? If so, discuss the problem with them and see if they will rebuild the carbs for you if that appears to be the problem.
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