I was winterizing my boat over the weekend and just wanted to make sure I put enough antifreeze in my engine, I have a 1990 Sea Ray with a 5.0 L. When I talked to West Marine they said about 4 to 5 gallons of antifreeze would work. So I put 4.5 gallons in the jug, started running it through the engine..noticed my temp started going up and no antifreeze being discarded, so I shut it down right away. I forget to open the vent cap on the jug so no air could get in..ugh I know not too bright. I don't know how much made it in but I don't think a lot. So put a little water too it, and got the temp back down. I started the process again and put the rest of the jug in..well almost all of it could not quite suck it all in. So I am thinking I got about 4 gallons (or a little less) in. Is that enough?. I live in Michigan so it will get below freezing, but I am storing it indoors. I don't know if that makes a big difference. I really don't want to pull it back out again and run more through. Any thoughts or suggestions would help.