When I change my oil on my 2009 Supra with the 340 indmar engine I use the drain hose and it come out very slowly, and end up taking about two hours to fully drain the oil. I make sure I run the boat for about 5 minutes to heat of the oil so I'm not sure why it is doing that. My buddies Moomba with the same engine only take 5 minutes to drain all the oil out using the same method.
So I was wondering if anyone have any solution to the problem. Coming up is going to be the third time changing our oil and hopefully will not take as long.