Have you been in such situation? When your diesel engine accidentally fall into water or was seriously beaten by rain to have water entering into the manifold? If yes, here is our gist on what to do.
Diesel engines suck air through their manifold and discharge the burnt gas through the exhaust channel in the form of smoke, for this reason when the air inlet (manifold is filled with water, the possibility of drawing water into the combustion chamber is 100% and if such happens the engine is doomed for serious faults. The fault associated with such problem ranges from inability to start, to the entrance of the water to the internal parts of the engine which may damage the oil mixture and cause other unknown errors in the engine.
When such a situation has arisen, ensure the crankcase of the engine is not turned until you have loosed the manifold and drain the whole water in it using rag to dry it up before trying to operate the engine again. That is the simplest way to handle such situation otherwise dismantle the combustion chamber if you feel the water had already entered there.