Sea Ray

Den, don't you have the engine factory service manual? If not, then that volume should be obtained. Always follow the FSM and applicable documents.

The FSM for my engines includes winterization steps: stabilizing the fuel; replacing raw water w/ freeze protection fluid; running oil w/ the fuel through the injectors; fogging the intake; running the fuel supply dry and ensuring all exterior metal is protected from corrosion.

There are many systems on the boat that need to be protected for the winter. Don't neglect the black water system. I keep that tank and parts scrubbed clean and that helps w/ winter protection.

IMO, the worst is the water heater. Mine holds about a gallon when run "dry" that dilutes the freeze fluid more than I like, so I plumb in a bypass so all the hot water lines and fittings get full-strength fluid.

A checklist was made by me for all the boat systems so I don't forget something important.