Water leak in transom plate

[yachtbarnestormer]

Hello everyone,
When we returned yesterday form the reef, I heard a trickling noise in the engine bay.
There is a machined hole in the ?'"transom plate"? that is letting in a steady stream of water from behind the starboard engine. About 1 gallon every 10 minutes at a guess.
Same hole behind port side engine is dry. See the photo below.
It was easily plugged as I need to be away for a week now, but can anyone identify the cause, is it a broken gasket that requires the engine to be removed? I assume this is the problem...
I had also noticed that this engine was running hotter than normal with lower oil pressure than normal?
Different problem?
Anyone with similar experience?
Thanks a lot, Barnestormer.

 

[GMAN1]

Looks like either a bellow split or the inserts for the trim senders are not seated properly. Either way - need to have it hauled out to avoid any more damage from the salt water intrusion.

 

[yachtbarnestormer]

Thank you GMAN,
Because of the logisitcs involved in hauling, (need to book a long time ahead, 30 miles to windward etc) I was also hoping if anyone thought this would require an engine removal?
Barnestormer