If you're looking at blue smoke it's not as likely to be the injectors. Injectors usually get linked to black smoke / an overly rich mixture.
Blue smoke is more likely compression related or somehow the lube oil blows by the rings and burns (It seals-up as the metal expands upon warming up) But it's not necessarily caused by worn-out cylinder / piston assemblies. It could be as simple as a using oil that's too thin for your engine and/or conditions or a valve / valve guide leak which can be fixed with a valve job and/or a top end cleanup / rebuild. From what I've read, quite common on sailboat diesels Here's some good reading on the subject: https://www.cruisingworld.com/how/read-those-smoke-signals https://www.boats.com/how-to/diesel-engine-smoke-blue-black-or-white/ I would have a competent local guy check it out. If the smoke is not persistent he will more than likely tell you to make sure you use fresh fuel / put some good fuel additives to prevent gumming and bacteria growth / keep the oil fresh / keep on sailing and don't worry. Good Luck, Francois Rivard
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