[Pretzel]

Very important! Do not crank the engine with the hose in the bucket of water or you risk getting water in places it shouldn't be (the cylinders, specifically). When the engine catches, THEN place the hose into the bucket.

Why would this cause any problem? When the boat is in the water, isn't that like having the hose in the bucket?

How does the water get into the cylinders from the cooling system?