Any advice as to the liklihood of restarting a 4 stroke engine after capsize?
I've dunked a small 2s engine twice (both times running). 1st time boat tured over and engine got swamped - was running when it went under and ended up full of water.
2nd time I was wearing the kill chord and the engine bracket broke on my little Avon 9ft. Engine fell of the back, stopped because of kill chord and was left dangling by the secondary attachment (ie rope). Got it back to shore and it started. The inside of the cowling was pretty much dry as there was obviously an air bubble inside the cowling preventing any water to get in (air vent holes are on underside). I did drain the fuel and re-fill as there was water in the fuel tank.
I guess whether the engine gets flooded depends on many things - position of crank when it stops (whether water can get into cyl via exhaust port or whether exhaust valve is open on 4str), whether the engine is running when it goes under (I assume if the boat inverts, engine will stop due to kill chord).
4 strokes are notoriously fussy about positioning of the engine to prevent oil draining out (ie which side you lay them on if transporting with a car). After a capsize, it's likely the sump oil is everywhere so may be a bad idea to try and start them without a good check over first.
The RNLI do (or certainly did) mod's to their 2-strokes to make them start after a capsize...