Ingress of water from stern when underway using the engine

Has anyone experienced a large ingress of water from the stern when underway in a seaway using the engine? My bilges both aft and midships flooded. Have spent a lot of time trying to locate the leak. Has anyone got any suggestions?

Hi Alon
I suppose you have checked the cooling water pump with the engine on - I had a leak due to the faulty bearing - but you must check the whole cooling circuit.
The propeler axis (going into the hull - in french the "presse etoupe") which might be the culprit. Otherwise the exhaust device (plastic made) on the starbard aft side of the engine that might be damaged, another leak can come from the bathing ladder ==> the supports are both going through the aft deck and are known to be prone to leaks... (almost impossible to access from the rear cabin).
Good luck !