I was trying to find a chart of the percentage of diesel engine hydrolock survivability. I should think that some military somewhere has one.
Though, I did find an actual submarine diesel repair manual, showing the repair components well enough to model:
https://maritime.org/doc/fleetsub/diesel/chap3.php
Oddly, it appears that some diesels had an extra inspection port that a main-bearing cap and connecting rod could be swapped.
As a thought experiment, it would seem that flooded engines offer some interesting game scenarios. None of this has to be modeled, but perhaps there could game-wise be...
Levels of water intrusion:
- Mist (Near the water surface, mist enters the intake)
- Sip (Single wave enters intake)
- Gulp (Intake is submerged for more than an instant
Levels of engine RPM:
- Idle
- Running Slow
- Running Fast
Yielding 5 levels of engine trouble:
- Sputter in warning, giving visible smoke to alert enemy
- Engine stall without damage, giving visible smoke. Water needs to be cleared (See below)
- Engine has minor damage. It runs with rapping sound and decreased performance
- Engine is damaged but can be repaired. Main bearing cap would be removed, if available, a new piston-connecting rod installed, taking an hour or so (each)
- Engine is irreparably damaged. Connecting rod penetrates engine block. Remaining engine, or battery power only
If the engine is not running, the engine cylinders would fill with water, same as a minor stall.
Stall Repair:
- Flame valves are opened
- Engine is cranked spraying water out, which would be humorous, if not for the destroyers
- Flame valves are closed
- Engine starts
Minor Engine Damage Repair:
- Engine runs with rapping sound and decreased performance.
Major Engine Damage Repair:
- Main bearing cap is removed.
- Piston, connecting-rod combo is taken from inventory or corner of the engine compartment
- Old piston and connecting-rod is removed
- New piston is installed, by wrenching at crankcase
- Main bearing cap is reinstalled
- (Same as above) Flame valves are opened
- (Same as above) Engine is cranked spraying water out
- (Same as above) Flame valves are closed
- Engine starts
Unrepairable Engine Damage:
- Engine cannot be repaired, connecting rod is shown penetrating the engine block
- Remaining engine can be used, if available, giving half the speed and charging
The Resources, if shown:
- Good piston-connecting rod model and texture. (I can make one if you need it.) This can just be an inventory thing that sits somewhere in the engine compartment
- Bad piston-connecting rod model and texture, same but bent connecting rod, which would be easier than a two-piece thing. This resource would also be toggled for engine failure, showing it penetrating crankcase.
- Main bearing cap with bolts still sticking out of it model and texture. (I can make it if you need it.)
- Water-spray particle-effect animation for the engine port. Perhaps I can make it, maybe.
- (Extra) a wrench or socket-wrench model, for a submariner repair animation. A submariner would sit at the engine wrenching at the bottom of the crankcase
- (Extra) damaged engine rapping sound. I could mix this in.
Going really far: In the long term, the crankcase oil needs to be changed, or engine degrades over time, for a campaign of something.
Perhaps it might be possible to damage an engine and it still run, with a rapping sound.