Re: cylinder head hoses
Use a sealant on the hoses. I've always used "Sealer 1000" which is manufactured by a company named "Marprox" or "Boat Armor Sealer 1000" which is the same substance. I'm not sure whether "Marprox" is still in business or not.
The same substance can be purchased from your local dealership. It used to be called "OMC Adhesive" but I'm unsure as to what Bombardier calls it. Of course this would be at a slightly higher cost.
Perhaps it is also available here at "iboats", worth checking into.